I N S T R U C T I O N S

Welcome to your Continental Academy course. As you read through the text book you will see that it is made up of the individual lessons listed in the Course Outline. Each lesson is divided into various sub-topics. As you read through the material you will see certain important sentences and phrases that are highlighted in yellow (printing black & white appears as grey highlight.) Bold, blue print is used to emphasize topics such as names or historical events (it appears Bold when printed in black and white.) Important Information in tables and charts is highlighted for emphasis. At the end of each lesson are practice questions with answers. You will progress through this course one lesson at a time, at your own pace. First, study the lesson thoroughly. (You can print the entire text book or one lesson at a time to assist you in the study process.) Then, complete the lesson reviews printed at the end of the lesson and carefully check your answers. When you are ready, complete the 10-question lesson assignment at the www.ContinentalAcademy.net web site. (Remember, when you begin a lesson assignment, you may skip a question, but you must complete the 10 question lesson assignment in its entirety.) You will find notes online entitled “Things to Remember”, in the Textbook/Supplement portal which can be printed for your convenience. All lesson assignments are open-book. Continue working on the lessons at your own pace until you have finished all lesson assignments for this course. When you have completed and passed all lesson assignments for this course, complete the End of Course Examination on-line. The End of Course Examination is C L O S E D - B O O K and must be P R O C T O R E D . This means, you must find someone to watch you take the exam. Your Proctor must be:

1. at least 21 years old 2. not a convicted felon, AND 3. NOT related to you

Be sure to have a Proctor available BEFORE you begin the examination. Once you pass this exam, the average of your grades for all your lesson assignments for this course will determine your final course grade. If you need help understanding any part of the lesson, practice questions, or this procedure: • Click on the “Send a Message to the Guidance Department” link at the top of the right side of

the home page

• Type your question in the field provided

• Then, click on the “Send” button

• You will receive a response within ONE BUSINESS DAY

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About the Author…

Dr. David H. Menke was born and raised in the St. Louis area. After high school, he enrolled at the University of California at Los Angeles, and over the next eleven years, earned his two bachelor’s degrees, his four master’s degrees, a teaching credential, and a Ph.D. in Science Education.

During his career, Dr. Menke has served as a public school teacher, community college instructor, and university professor. He has worked full time at such institutions as California State University, Northridge; Southern Utah University; Central Connecticut University; and Broward Community College. Much of his career was spent as an academic administrator of public observatories and planetariums.

Dr Menke serves as the First Vice-President and COO of the International Planetarium Directors Congress, and as Chief Astronomer for the Sossusvlei Mountain Lodge in Namibia, Africa. As a world traveler, Dr. Menke has served as leader of many expeditions, including observations of eclipses and comets – on land and at sea. Dr Menke speaks, reads, and / or writes 16 languages.

Dr Menke is married and has six children and 4 grandchildren. Dr Menke’s wife is an elementary school teacher and mental health counselor.

Physical Science by David H. Menke, Ph.D.

Copyright 2008 Home School of America, Inc.

ALL RIGHTS RESERVED

For the Continental Academy Premiere Curriculum Series

Course: 2003310

Published by

Continental Academy 3241 Executive Way Miramar, FL 33025

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FORWARD to PHYSICAL SCIENCE Keep these two thoughts in mind…. “Science is a way of thinking much more than it is a body of knowledge.” - Carl Sagan (1934 – 1996), American Astronomer “All our science, measured against reality, is primitive and childlike-and yet it is the most precious thing we have.” – Albert Einstein (1879 - 1955)

German-American Physicist

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TABLE OF CONTENTS

Forward ....................................................................................................................... 4 Lesson 1 The Scope of the Physical Sciences ............................................................. 7 Lesson 2 Mechanics: the Dynamics of Particles & Systems ..................................... 15 Lesson 3 Electricity & Magnetism ............................................................................. 35 Lesson 4 Nuclear Physics ........................................................................................... 47 Lesson 5 Physical Chemistry ...................................................................................... 53 Lesson 6 Organic Chemistry ....................................................................................... 63 Lesson 7 Unified Field Theory ................................................................................... 73 Course Objectives ............................................................................................. ……… 85 Appendices ...................................................................................................... 91 Appendix I.................................................................................................. Glossary Appendix II……………………………………Physical Science Labs Appendix III……………………………………Solutions to Study Questions Appendix IV…………………………………….Great Scientists

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LESSON 1

THE SCOPE OF THE PHYSICAL SCIENCES In this Lesson, you will get a feeling for our place in space, among the moons, planets, stars, and galaxies. You will also understand the similarities and differences between time and space. The Lesson includes: One’s place in the Cosmos Direction of Time and Space ONE’S PLACE IN THE COSMOS The Cosmos is another way of saying “the universe.” The word “universe” means “everything in our one existence” as “uni” means “one.” Examples A unicycle is a one-wheel “bicycle.” The “union” is another name for our 50 uni-ted, or uni-fied states. To be “uni-que” means “one of a kind.”

To understand the universe and our place in it, we must examine the laws of the universe, which apply everywhere. And that is what we will do. We will study the same laws that were studied thousands of years ago, but we will have a more modern up-to-date perspective of what they really mean to us. Early scientists, like Aristotle, were brilliant, but they did not understand the laws as well as we do today.

Example A “law” is a rule that we must live by. We humans make laws to govern and run our cities, our states, and our nations or

countries. Whereas the laws of the land are made by people, the laws of the universe, sometimes called the laws of nature, are not made up, but are eternal, and apply everywhere. It is usually up to us as intelligent beings to discover what those laws are.

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We start our adventure by realizing that there are two ways of looking at the universe. First, we look at ourselves, and everything beyond us to the ends of space and beyond – the multiverse. Second, we look at ourselves, and everything inward on Earth to the smallest sub-atomic particle – the quark. While there are millions of types of plants and animals on Earth, and there are many intelligent animals, humans are the most intelligent and the most advanced. Dolphins are intelligent, but they cannot build space ships or wristwatches or radios.

Examples Even though in the movies and on television animals are portrayed as being able to speak English and other languages, drive cars, and do many other things, these are merely stories. And these stories are make believe, or fiction. Humans and all other life forms are real, they are facts. We can talk, ride bicycles, and travel to the Moon. Dogs cannot speak (well, they bark), they don’t ride bicycles, and certainly cannot travel to the Moon, unless we humans send them there. And plants can do even less. The next most intelligent animal on Earth is the chimpanzee. In fact, chimpanzees

are even brighter than dolphins, but they still are not able to create architectural monuments or have rapid transit. For whatever reason, we humans have delved into the unknown to discover the laws that govern the universe.

These laws are essentially the laws of physics. Both Astronomy and Chemistry are parallel, and quite similar, branches of Physics, and they are included in this textbook. However, a more in-depth study of Astronomy is covered in another course entitled “Earth and Space Science.” The planet Earth is the only one in the Solar System with intelligent life forms. Other planets, such as Jupiter, may harbor simple life forms, like bacteria. But Earth is the only one with complex animal life forms with massive reasoning power. And if you are reading this, then you are one of them.

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We humans are a curious lot. We always want to learn, to understand, to predict, to control. And studying the Physical Sciences helps prepare us to do just that. We humans are also very complex, with over a billion moving parts, yet humans are made of the simplest and most common raw materials on Earth. Even so, humans run on solar (Sun) energy – indirectly anyway. And the Sun is a star. Our star. It is a huge ball of hot gas – a nuclear burning furnace. But it still must obey the laws of science that will be covered in this course.

In sum, we are one of billions of life forms on Earth, albeit the most intelligent. We are not the largest, nor the smallest. But we do dominate the planet. Our planet, Earth, is the 3rd planet from the Sun, and our star, the Sun, is only one of some 400 billion stars in the Milky Way Galaxy. In turn, our galaxy, the Milky Way, is only one of millions of galaxies in the Universe. And, well, the Universe may be only one of an infinite number of similar universes throughout all of time and space; this is called the multiverse. And our next lesson begins with time and space.

Key Terms and Concepts • universe • planet • galaxy • sun • intelligent life • fact vs. fiction

Problems 1. How many numbers can fit in between the numbers 1 and 2? 2. How many galaxies can fit in to the universe? 3. What is the most intelligent life form on Earth? 4. Give a reason to support your answer to #3. DIRECTION OF TIME AND SPACE Time Time is measured by clocks, watches, and other devices called “chronometers,” or “chronographs,” or time pieces. The word “clock” comes from the Latin word clocca, which means “bell.” In olden days, a clock tower would ring a bell every hour. The Greek word krono means “time,” and a meter

measures, while a graph records, so any time piece may be referred to as a chronometer or chronograph. The word “watch” comes from an old English phrase, waeccan, which means “watchable,” or “worth watching” or “worth looking at.” In nautical, Greek, and Roman terms, a person’s “watch” meant his “period of being on duty.” Therefore, we

measure out time with a small time piece called a watch.

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The basic Lesson is the second, and there are 60 seconds in a minute. Coming from the Latin word, secundum, which means “division of time,” we divide an hour into minutes and seconds. One might expect that the word “minute” would also come from Latin, and it does. Minuta in Latin used to mean “very small division of time,” which it is. Of course, a second is even smaller.

The length of the second probably came about since the human heart beats approximately 60 times in one minute – or once per second. Thus, our measurement of time is based upon a natural biorhythm. Example Try this simple experiment. Use a watch or clock to determine your heartbeat rate. Find your pulse (in your wrist or in your throat area), and then count the number of pulses during a 60-second period. When a person gets nervous or afraid, the pulse rate goes up. If your pulse rate is very high, you may wish to consult a physician.

Time Zones Earth is a sphere, and as such, has a circumference of 360 degrees – just like a circle. Scientists divided up these 360 degrees into 24 different time zones, each approximately 15 degrees wide. The time zones would begin in Greenwich, England, at 0 degrees, and increase by one hour of time for each 15 degrees eastward one would move. Also, the time would decrease one hour for each 15 degrees that one might go westward. Before Time Zone Laws went into effect, each town, village, and city had its own time, based upon the position of the Sun. Example - In the old days, when each town had its own time, it would be like this - in Boston, Massachusetts the time might be 12:10 PM, while in Hartford, Connecticut it would be 12 Noon, and in New York City, it would be 11:50 AM. Now that time zones have been “standardized,” it means that every town and every city within the same time zone has the same time on their clocks. Examples - Every town from Bangor, Maine to Miami, Florida, is on the same time zone. This is called the Eastern Time Zone, or Greenwhich minus 5 hours. The continental United States has 4 time zones: Eastern, Central, Mountain, and Pacific. Of course, when one includes Alaska and Hawaii, that adds more time zones. Canada has 5 time zones – 4 that are exactly the same as the ones in the continental U.S., and 1 more – a time zone for the Maritime Provinces of Nova Scotia, Prince Edward Island, and New Brunswick. These provinces are east of the Eastern Time zone, and are in the Atlantic Time zone, which is one hour ahead! Canada’s Maritime Province of Newfoundland has its own time zone, one-half hour ahead of the Atlantic Time Zone.

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Other nations are also a half hour different from their nearby time zones. These countries include Iran, Afghanistan, India, Iraq, and other nations in that area. In fact, the small country of Nepal is 45 minutes different! While England is on the Greenwich time zone, most of western Europe is one hour ahead – except for Portugal. So, Spain is one hour ahead of Portugal! Daylight Savings Time Daylight Savings Time (DST) is a plan for setting clocks 1 (or 2) hour(s) ahead so that the sun both rises and sets at a later hour. This gives an additional hour of daylight in the evening – used mostly during summer months. Daylight Savings Time was first introduced by the American Statesman Benjamin Franklin in 1764. Later, it was advocated by a Briton, a one William Willett, in 1907. Daylight saving has been used in the United States and in many European countries. During World War I, DST was adopted in order to save energy. Some places returned to standard time after the war, but others kept DST. The U.S. Congress passed a law during World War II that placed the entire country on “war time,” which set clocks 1 hour ahead of standard time. “War Time” was also followed in the United Kingdom, where clocks were put ahead 2 hours during summer months. In peacetime, DST was controversial. Farmers were inconvenienced when they had to conduct business on a different time schedule. Railroads, bus companies, and air line companies had scheduling problems due to inconsistencies in various cities and states. In 1966, Congress passed a law called The Uniform Time Act, which established a system of uniform daylight saving times throughout the states, exempting only those states in which the state legislature voted to keep the entire state on standard time. The states of Arizona and Hawaii do not have DST; parts of Indiana also do not have DST. Since 2007, DST begins at 2 AM on the second Sunday of May and ends at 2 AM on the first Sunday of November. But what is time and what is its purpose? In the science of relativity - discovered by Albert Einstein - we say that “time separates events in space.” In other words, if we were to observe a specific location in the universe, we might notice a variety of “events” occurring over time. The only thing that separates these “events” is time itself. Example - A simple example might be a classroom in any school. Let’s say that Mrs. Jones has a 1st period class in the subject of English, every weekday during the school year. Let’s say that 1st period runs from 8:00 AM to 8:55 AM. Let’s also say that Mrs. Jones has a 2nd period class in another subject, like Creative Writing, and it runs from 9:00 AM to 9:55 AM.

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Let’s also say that Mrs. Jones holds these two classes in the exact same room, Room 202. Thus, Room 202 is defined as a “space.” Each school day there are many distinct “events” in that space (in Room 202). Event 1 is a lesson in English with a certain group of students. Event 2 is a lesson in Creative Writing with a completely different cohort of students. Event 3 may be an “empty” classroom with nothing going on, and so forth. Perhaps that would be Mrs. Jones’s planning time.

The only thing that separates these three events (the two groups of students and the planning period) is time. The space is the same. The teacher is the same. If time had no meaning, or did not exist, then we might expect anything and everything happening in this space in any order. That would be chaos – another branch of physics. Time is an entity measured by timing devices called chronographs or chronometers. These include clocks, watches, and other similar tools, including candles and sundials. Time always moves forward, into the future, coming from the past, and is always in the present. Time never moves backwards, except in science fiction. In this manner, we refer to time as being one-dimensional. While time is measured in units of seconds, there are also many other units of time, developed for convenience, such as minutes, hours, days, weeks, months, years, decades, centuries, millennia, and aeons. We can also divide the second into milliseconds, microseconds, and even smaller units. Space While we often refer to the word “space” when talking about stars and galaxies, out in “space,” in reality, “space” is a far more important concept. While Time is one-dimensional, Space, on the other hand, is three-dimensional, or 3-D. An artist or an architect would say, “height, width, and depth.” Height is the up and down dimension, sometimes called “the y-axis.” Width is the left and right dimension, sometimes called “the x-axis.” And, finally, depth is the in and out (or backwards and forwards) dimension, often called “the z-axis.” We can go up and down, left and right, backwards and forwards.

Space has the units of length, width, and height, or volume. In science, volume is in the units of liters. Remember that 1000 mL = 1000 cc = 1000 cm3 = 1.0 liter. This would be the volume of a cube with a length of 10 cm, width of 10 cm, and height of 10 cm. When we use only two axes (we pronounce this work “ax-eez,” so as not to confuse it with the plural of a tool called an “ax”) say, the x-axis and the z-axis, then that entity is called a “plane.” Don’t

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confuse this with an airplane or a field, like a plain in Kansas. The entity is just a “plane.” The x-z plane is a two-dimensional entity that is a geometrically flat surface – such as a table top. The top of a table is 2-D. The table itself may also have legs, and thus, have components that are 3-D and into the y-axis, but in this case, we are referring only to the surface of the table. A sheet of paper is also 2-D. Well, the surface of the paper is. Of course, the sheet has a slight thickness, but very slight – adequately slight to be sharp enough to cut one’s skin (a paper cut). While science fiction often talks of 4 or 5 dimensions of space, we humans cannot grasp what that may be. Even so, human scientists such as the late Carl Sagan, often discussed the possibility of such dimensions, and how interesting that they may be. Thus, for now, we recognize only four dimensions: the 1-D of time, and the 3-D of space. This is called “the fabric of space-time,” and it will come up later. Key Terms and Concepts • units of time • units of space • fabric of space time • definition of time • definition of space Problems 1. What time is it? How do you know? 2. Research and explain the many time zones around the globe 3. What is the history of Daylight Savings Time? 4. Where on Earth is it exactly 12 hours ahead of where you live?

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LESSON 2

MECHANICS: THE DYNAMICS OF PARTICLES AND SYSTEMS In this Lesson, you will begin to grasp the “nuts and bolts” of the science of physics, including distance, speed, acceleration, momentum, heat, and waves. The Lesson includes: Weights and Measures (Lab 1: Density of Water) Motion – Velocity and Acceleration (Lab 2: Motion in One Direction and Lab 4: Acceleration) Energy, Force, and Momentum (Lab 3: Motion in Two Directions) Heat and Temperature Waves – Light and Sound (Lab 5: Speed of Sound) WEIGHTS AND MEASURES (During this lesson, do Lab 1: Density of Water) In the physical sciences, we are continually measuring things. The basic measurements include length (or distance) and mass (or weight). We measure lengths with rulers, meter sticks, measuring tapes, and various other tools, including micrometer calipers for very short distances. The standard unit of length is the meter. A meter is about the same length as a yard. However, a meter is defined as part of the Earth itself: the distance from the equator to the Geographic North Pole is exactly 10 million meters.

The yard was the distance of some British king’s arm, so we don’t find that very scientific. Plus, the yard is also equal to three feet, presumably some royal person’s foot length.

Example There’s a story of a grandma sitting on a porch and knitting 3 socks. “Why are you knitting 3 socks?” asked a neighbor. “Well, my grandson told me that he has grown a foot since he’s been in the Army!” Of course, there are units larger and smaller than the meter. For example, 100 centimeters is equal to 1 meter. This is just like 100 cents is equal to 1 dollar. As a comparison, 2.54 centimeters equals 1.0 inch, and 12 inches equals one foot.

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And 1,000 millimeters is the same as 1 meter. Although not used in society any more, there used to be coins called mills that were 1/10th of a cent. A total of 1000 mills equaled 1 dollar. These mills were used in the old days to pay taxes when the tax on some item was less than a penny. Most mill coins were made of plastic. On the other end, 1,000 meters is equal to 1 kilometer, from the word kilo, which means “thousand.” As a comparison, 1.6 kilometers equals 1.0 mile, or 1.0 kilometer is about 5/8th of a mile.

People who study the physical sciences use units as small as a nanometer, an Angstrom, a picometer, and other tiny units; and they use units as large as megameters, light years, parsecs, and kiloparsecs. In your study of the physical sciences, you will run across these terms.

At this juncture, one may ask, “what is wrong with inches, feet, yards, and miles?” Well, nothing really. But science likes to use units based upon constants, not on the length of the arm of the local king. Plus, one may notice that all the metric units are in powers of ten. This decimal system is much, much easier to use than the old system. As another thought, realize that 12 inches equals a foot. Not 10 inches. And that 3 feet equals a yard. And 5,280 feet equal one mile. It’s all a mass of confusion. The decimal system, usually called the metric system, is not complicated or confusing at all.

When we begin to measure the weight, or mass, of an object, we again use units in the metric system. For example, the unit of mass is the kilogram – or 1,000 grams. Each kilogram weights about 2.2 pounds at sea level on Earth. But a kilogram, or a gram, measures mass, not weight. Mass never changes over time or space, while weight is really a force, and it is different at each place in space. Example - If you weighed 120 pounds on Earth, you’d weigh only 20 pounds on the Moon. You wouldn’t be thinner, or look any different, but the force of the Moon’s gravity on you (your weight) would be less. However, if you were 55 kilograms (120 pounds) on Earth, you’d still be 55 kilograms on the Moon, or anywhere else.

Mass is merely the amount of matter, not how the matter is affected by a gravitational force field. For convenience, we often say that 1.0 kilogram equals 2.2 pounds. But what we really mean is that 1.0 kilogram weighs 2.2 pounds at sea level on the planet Earth. Example - How much is your mass? Find a bathroom scale, “weigh” yourself, and divide that number by 2.2. This will give you your own mass (in kilograms). The rest of the world uses this, why not you?

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In sum, we scientists use the units of seconds, meters, kilograms, and other units related to those, either powers of ten higher, or lower. Key Terms and Concepts • metric system • mass • weight • length • units in the old system • units in the metric system • powers of ten Problems 1. Convert 5-foot, 10-inches into centimeters 2. Convert 200 pounds into kilograms (on Earth) 3. How many grams are in a kilogram? 4. How did we get the unit of the “yard”?

MOTION: VELOCITY, AND ACCELERATION (During this lesson, do Lab 2: Motion in One Direction and Lab 4: Acceleration) If an object is NOT moving at all, then it has a set of coordinates, i.e., a place in space which is identified with x, y, and z coordinates (recall the conclusion of Lesson 1.2). Example - The city of Ft. Lauderdale, Florida, has a set of coordinates that pinpoints, on Earth, where it is. These are the latitude and longitude. Ft. Lauderdale is approximately 26 degrees north and 80 degrees west. This means it is 26 degrees north of the Equator, and 80 degrees west of Greenwich, England. The z coordinate would be elevation (feet above sea level) of 6 feet. However, very few objects are merely stationary. Even Ft. Lauderdale is moving – relative to space. It is on Earth’s surface while Earth is rotating at some 1600 kilometers per hour (about 1,000 mph). Plus, Earth is revolving around the Sun, at about 30 km/sec (about 20 miles/sec). Thus, even though the city of Ft. Lauderdale is not wandering around Earth’s surface, yet, it is still in motion.

Thus, any and every object is moving. And if it is moving, then it has a speed, or velocity. It may also have acceleration. The speed of an object is a measurement of how fast it is going – usually relative to Earth’s surface. For example, one may drive his car at 60 miles per hour. This gives the speed, which is the distance traveled over the period of an hour (assuming that the speed is always at 60 for the entire hour). However, in the physical sciences, we care more about meters per second.

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The fastest speed anything can go is the speed of light, often symbolized by the letter “c.” Light travels at the incredible speed of about 300,000 kilometers per second, or 300 million meters per second (about 186,282 miles per second). At this amazing speed, one could travel around Earth seven times in one second; to the Moon in 1 ¼ seconds. To the Sun in 8 minutes. To Pluto in 5 hours. To the nearest star in just over 4 years. Even so, the speed of light is not infinite, as Galileo first believed. Thus, everything else in the universe travels slower than the speed of light. Example - So, let’s imagine that you are driving a car down the highway at a speed of 60 miles per hour. Let’s change that into kilometers per hour: 60 miles is equal to 96 kilometers. Thus, the speed is 96 km/hr. How fast is that in kilometers per second? There are 3600 seconds in an hour, so 96 km/3600 seconds equals 0.0267 km/sec, or 26.7 meters/second. In the physical sciences we are more interested in velocity, rather than speed. What? You say. Isn’t it the same thing? Yes, and no! Both measure how fast one is going. But velocity also includes the direction that the object is going. Example - A speed may be 60 miles per hour (or 26.7 meters per second), but a velocity would be 60 miles per hour north (or 26.7 meters per second north). Notice that a direction is added on to the speed to make it a velocity. That’s really the only difference between speed and velocity. Or, speed + direction = velocity. Once a direction is added to a speed, then the entity becomes a vector. A vector can be thought of as an arrow. No competent archer or woodsman would shoot an arrow at random. He would shoot the arrow towards an object, whether a deer, an enemy, or a practice “bull’s-eye.” Airline pilots also use the term “vector” to determine what speed and direction that they are flying their airplanes. Acceleration Now let’s talk about acceleration. Pretend that you are in a car, and you are ready to pull out of the driveway onto the street. In order to make your car “go,” you will have to step onto a floor pedal called the “accelerator.” You would never step on the brake pedal or some other pedal in order to “go.” But why is this pedal called the accelerator (also known as the “gas pedal”)? Because when one pushes this pedal, the automobile speeds up – i.e., it changes its velocity or its speed. When you push down on the accelerator, you speed up, or, in other words, you accelerate. Example - The term “acceleration” means that you are changing the speed, or velocity, over time. You may be traveling at 30 miles per hour, but then choose to speed up to 50 miles per hour. That means that you will have to increase your speed from 30 miles per hour to 50 miles per hour – or a difference of 20

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miles per hour. And how long will it take you to do that? Let’s say it takes 10 seconds. Then you will have an acceleration of 20 mph/10 sec = 2 mph/sec. In the physical sciences, we don’t use the units of miles per hour per second. Rather, we use meters per square second. No, there is no such thing as a “square second” as there is a unit called “square feet.” But it is a term that we use, meaning, seconds per second. Instead of 2 miles per hour per second, we’d say so many meters per second per second (0.89 m/sec/sec), or, for convenience, 0.89 meters per second squared. We also would write it 0.89 m/s2. It’s just a phrase we use for convenience. So, in summary, distance is in meters, such as length along the x-axis. Speed or velocity is distance (in meters) per second, such as meters/second, or v = x/t along the x-axis, where “t” is the time in seconds. And acceleration is the change of speed or velocity over time, or (v/t) = (x/t)/t = x/t2. Note that here “v” represents the change in velocity (speed). Acceleration is the change of velocity over time. Remember, velocity is speed plus direction. So, if an object’s direction of motion changes, but its speed does not, that object still is accelerating. How can this be? Whenever an object’s motion follows a curved path without speeding up or slowing down Key Terms and Concepts • motion • rotation • revolution • length • meters • speed • velocity • meters per second • acceleration • meters per square second Problems 1. Assume that the equator of the Earth is 24,000 miles long (that’s its circumference). Now, pretend

that you are standing somewhere on the equator, such as in the country of Ecuador. Now, if the Earth turns once, completely, in 24 hours, then, how fast would you be going, even if you just stood still?

2. If your Aunt Mary lived 100 miles from you (by car), how fast should you drive your car (on average) to get to her house in 2 hours? 90 minutes? 1 hour?

3. Now, imagine that you take a road trip of 80 miles, from A to D, but you have to do it in segments. Let’s say you drive from A to B in 30 minutes, B to C in 45 minutes, and C to D in 15 minutes. The distance from A to B is 15 miles; from B to C is 45 miles, and C to D is 20 miles. How many miles did you drive from A to D? How many minutes did it take you to drive from A to D? Convert all those minutes into hours, by dividing by 60 – how many hours did it take you to drive from A to D? What was your average speed during your trip from A to D (divide the total miles by the number of hours).

4. A race car driver speeds up from 60 miles per hour to 90 miles per hour in 3 seconds. What was his/her acceleration?

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ENERGY, FORCE, POWER, AND MOMENTUM (During this lesson, do Lab 3: Motion in Two Directions) MOMENTUM In Latin, the word momentum meant “moving power.” In the physical sciences, momentum is quite simple; in a way, it is the energy of motion. Here, it’s the mass of an object multiplied by its velocity (therefore, it has a direction, and is a vector). Momentum is symbolized by the letter “p,” so p = m x v, where “x” means “multiplied by.” Here, “v” stands for velocity, not a change in velocity. Examples: If a 1.0-kilogram object were traveling north at 30 m/s, then the momentum would be 1 x (30) = 30 kg-m/s. Yes, a “

smkg − ” is a strange unit, but you can’t have everything.

A slow moving bowling ball of a mass of 10 kilograms and a fast moving marble of a mass of only 10 grams = 0.01 kg would have the same momentum if the bowling ball were traveling at 10 m/s and the marble were traveling at 10 km/s! A fast moving marble can pack a wallop! It is similar to a bullet, which weighs almost nothing, but travels about 500 meters/second.

In society, we often use the term “momentum” to mean the energy of motion of a person or a cause. For example, in 1991 and 1992, Bill Clinton, then-governor of Arkansas, was able to develop political “momentum” that propelled him into the White House. At first, nobody believed that he had a chance, but he never gave up, and his momentum was so great, in the end, nobody could stop him. There is also a similar type of momentum called angular momentum. In this case, it’s the momentum of an object in motion around another object, such as the energy of motion of Earth around the Sun. The value of angular momentum is equal to the object’s mass, “m,” multiplied by the object’s velocity, “v,” multiplied by the distance, “r,” the object is from the main object (such as Earth’s distance from the Sun). In other words, the angular

momentum, symbolized by the letter, l, equals mass (m) times velocity (v) times radius or distance

(r), or l = m x v x r. The units of angular momentum are “s

mkg 2− ,” which is another strange type of

unit.

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FORCE The Latin word fortis, which meant “strong,” evolved over time to become the word “force.” Isaac Newton, a British scientist, spent much of his life studying force. In fact, Newton developed the Three Laws of Motion, which included the concept of force. Newton was a rare kind of thinker; he was a genius (See Appendix 4). Originally, the Laws of Motion were discovered in the year 330 BC by the Greek thinker, Aristotle. He had stated:

1. Objects in motion come to rest 2. Objects that go up, must come down

Later, in the early 1600’s, both astronomers Johannes Kepler (a German) and Galileo Galilei (an Italian) also studied these laws. In the late 1600’s, Newton developed three, not two, laws:

1. Objects in motion stay in motion, unless an unbalanced external force is applied 2. The amount of force is equal to the mass of an object multiplied by its acceleration,

or F = m x a 3. Every action (force) has an equal and opposite reaction (or force)

Which brings us to the concept of force. As defined above, a force, F, applied to an object of mass, m, would then accelerate the object at a rate of a. Necessarily, if the mass is very, very high relative to the force, then the acceleration will be very, very small, perhaps even close to zero. For example, if a human exerts a force on a huge concrete building, it won’t move much, thus it’s acceleration is, well, zero. Example - You already know that distance is measured in meters, but you may not know that force is measured in units of Newtons. Since much of Newton’s work dealt with the laws of force, the unit of force was named a “Newton,” in his honor. The unit, Newton, is equal to kg-m/s2. Thus, we define 1.0 Newton = 1.0 N = 1.0 kg- m/s2. When a baseball pitcher, or a football quarterback, or any other such player exerts a force on a ball, it leaves the hand and quickly accelerates to some maximum speed. The planet Earth exerts a force on all objects near it. This is the gravitational force. The force of gravity is equal to the mass of the object (such as your mass) multiplied by the acceleration due to the gravity of the planet; in this case, it’s Earth. You can find out the acceleration of gravity very simply using a piece of string, a metal washer, a ruler, and a stopwatch. As it turns out, the acceleration due to gravity on Earth is 9.8 m/s2 (or 32 ft/s2). This means that if one dropped a marble off the top of a 10-story building, it would keep increasing its velocity at the rate of 9.8 m/sec every second. So would a bowling ball.

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Newton derived the Law of Gravity as part of his Second Law. This originally was derived from Kepler’s 3 Laws, and it has the form of: Fg = G (m x M) / r2 Where Fg is the force of gravitational attraction (in units of Newtons) between any 2 objects of masses “m” and “M” whose centers are “r” apart. The large “G” is called the Universal Gravitational Constant, and is equal to the number 6.7 x 10-11 N-m2 / kg2. Newton did not know this constant; it was determined more than 50 years after Newton’s death by a British scientist named Henry Cavendish. The small “m” stands for the mass of the lighter object (like the mass of a human); the large “M” stands for the mass of the heavier object (such as Earth’s mass), and “r” is how far the centers of the two masses are apart. For Earth, that would mean r = radius of Earth, which is about 6400 kilometers. As you stand on the Earth, your center (maybe your navel) is about 6,400 kilometers away from the center of the Earth. In the above equation, r is squared. Thus, the whole equation is: Force of gravity is equal to a constant, G, multiplied by the product of m and M, and all of that is divided by the square of the radius. This is the force of attraction between any body of mass, m, and any other body of mass, M. Notice that

Fg = G (m x M) / r2 = m x a, or Newton’s 2nd Law,

where a = (G x M) / r2 = 9.8 m/s2 is the acceleration due to gravity on Earth. Each planet has its own force of gravity because, well, each planet has its own size and its own mass. ENERGY Energy, from the Greek energos, meaning “active,” is expended when an exerted force moves some object. In other words, if you push a baby stroller the distance of 100 meters, then first you had to exert a force on the baby stroller, and it had to move a certain distance. It took energy for you to push that stroller. Energy has the units of joules. Say what? This is because a man named Professor Joules studied energy. Anyway, energy comes in many forms: heat, light, electricity, mechanical, acoustical, and so forth. However, no matter what, the units are joules. And joules are really units of force x distance. In a formula, that would be E = F x d. The concept of energy is very straightforward. If you apply a force to an object, and if the object moves, then you have expended (or used) energy. The measure of energy is force multiplied by distance, or E = F x d. Hmmm… didn’t I just say that a few lines up? Well, it was worth repeating.

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Example If I exerted 1.0 N of force on an object and if I were able to move that object a distance of 1.0 meter, then the energy that I expended would be (1.0 N) x (1.0 m) = 1.0 Newton-meter, which is defined as a Joule, named for James Joule, a 19th Century British Scientist. Energy can be expressed in many ways, and there are many forms of energy. There’s gravitational energy, potential energy, kinetic energy, thermal energy, electrical energy, acoustical energy, light energy, mechanical energy, nuclear energy, and so forth. Their units are all in Joules, but occasionally one hears of other units of energy, such as ergs, electron volts, calories, and so forth. Potential energy (PE) is energy that is stored and available to use in some way, such as the electrical energy stored in a battery. Gravitational potential energy (GPE) is nothing more than the energy’s potential at a certain altitude, i.e., gravitational energy equals the mass times the acceleration due to gravity times the distance that an object can fall, or

GPE = mgh, where m = mass, g = m/s2, and h = the distance that the object can fall. This is why waterfalls are excellent sources of gravitational potential energy, and such natural phenomena are harnessed to change the gravitational potential energy into hydro-electric power (“hydro” means water). Kinetic energy (KE) is the energy of an object as it is traveling at a certain velocity. The word “kinetic” comes from the Greek word kinetikos, which means “to move.” The relationship to determine how much kinetic energy an object has is

KE = ½ m v2 This means that an object of mass, m, has a kinetic energy, KE, equal to ½ its mass, multiplied by the velocity, v, squared (or v x v = v2). Remember to square the object’s velocity before multiplying it by half of the object’s mass. Thermal energy (TE) is the amount of energy an object has due to the heat stored in it. This concept will be covered in more detail in the section on Thermodynamics in Lesson 4. However, just to give a relationship,

TE = 3/2 k T where “k” is a constant, and T is the temperature of the object in absolute degrees, or in what we call in Kelvin temperature. Electrical energy (EE) is the amount of energy in an electrical system, and its value is

EE = q V where “q” is the electrical charge value, and “V” is called the potential. In other words, V is sort of like the potential energy stored up that can be used. In electricity, we usually use the energy units of electron volts. This will be covered in more detail later on.

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Acoustical energy (AE) is the energy of sound, and this is covered in Lesson 5. Light energy (also known as electromagnetic radiation, or EMR) is the energy stored in a particle of light (or a wave of light) and this is covered both in Lesson 5, and in Unit 3, Lesson 4. In brief, the amount of light energy is equal to a constant multiplied by the frequency of the light itself, or

E = h v, where “h” is called “Planck’s constant,” for the German scientist Max Planck. The symbol, “ν,” is from the Greek letter for “n,” and is called “nu.” This sounds just like “new.” And this symbol stands for something called “frequency.” One of the laws that we will learn is that the speed of light, symbolized by the letter, “c,” is not only a constant, with a value of about 300,000 km/s, but it is equal to the wavelength of the light, λ, multiplied by the frequency of the light, ν. In other words,

λ x v = c While all these terms will be covered more extensively later, just be aware of these them. Mechanical energy (ME) is the energy that can be applied to build, destroy, re-shape, or move an object – such as the energy that a bowling ball would release if it fell 10 stories to the street below. Shortly after impact, both the bowling ball and the concrete sidewalk would be broken and smashed – due to the mechanical energy that was released. There is also an energy called “nuclear energy” or NE. There are several forms of this, but suffice it to say that it is similar to gravitational energy of a planet orbiting the Sun, or a moon orbiting a planet. This energy deals with both a relatively weak force and a strong force. Inside the nucleus, there is tremendous energy that keeps the nuclear particles “stuck” together. This is a very powerful force. If one releases this energy too quickly, it becomes an atomic, or nuclear, bomb. Finally, another form of energy is “work.” Essentially, if you do work on something, then you expend energy. Thus, Force times distance = work, and the units are joules. However, if the object did not move (distance = 0), then work = 0, W = F • d = F • 0 = 0. No matter how much force was applied. Example - We often say that we are “going to work” and then we leave our homes for many hours, while we are at “work.” When you are at work, do you really do any “work”? When you exert some sort of force, do you move something, or, in other words, get something accomplished? POWER Finally, we have mentioned “power” a few times. The word, “power” comes from a Latin word posse, which means “to be able to.” This word later evolved into the French word, “pouvoir,” which also means “to be able to.” Eventually this became the word “power” in English. Power is equal to the amount of energy that one uses per unit of time, i.e., joules per second. In fact, the unit of power is the Watt, named after yet another scientist, a Scot named James Watt (1736 – 1819).

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In any event, if one can expend a lot of energy (or do a lot of work) in a short period of time, then that person is very powerful. The relationship is:

P = E/t

where P is power, E is energy, and t is time. Examples - Imagine that you were given the job to dig a hole, eight feet long, six feet deep, and three feet wide. It would take a lot of “work” for you to do this; you’d expend a lot of energy. And how much time would it take you? Maybe 8 hours, if the weather were good and if you could keep going without interruptions. Now imagine that a much stronger and more energetic man could dig an identical hole and that he could do this in 10 seconds. Amazing, huh? While a fictional character like Superman could do it, a real person could not. Even so, Superman is called “super” for a reason. While both you and Superman would do the exactly same amount of work, and expend the exact same amount of energy, since Superman could do it much faster, it would show that he was more powerful. Time means power. Well, short times mean more power. And you would have to agree that any person who could dig a hole faster than you would have to be more powerful than you are. A similar concept occurs in society. If you were to be at work and merely said, into the air, “Gee, I’d like a turkey sub sandwich,” how long would it take for someone to go get you such a sandwich, if ever? Now, if you were president of the United States, and you were at work with others around you, and you said, into the air, “Gee, I’d like a turkey sub sandwich,” do you think someone would go get the president such a sandwich? Here’s another example. Let’s say that you are angry with some dictator in another country, and that you write the dictator a letter, telling him to “be nice” or he will have to answer to you. Will the dictator be worried? What if the president of the United States were to tell the dictator to “be nice” or answer to the U.S.? Would the dictator have more worries and concerns than he did over your letter? Who has more “power”? You, or the president of the United States? Key Terms and Concepts • momentum • units of momentum • angular momentum • force • energy • work • power • Newton’s Three Laws of Motion • The Law of Gravity

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Problems 1. What is the momentum of a 2000-pound car traveling at 30 miles per hour? Give the answer in

metric units (change pounds to kilograms; miles per hour to meters per second). 2. What is the angular momentum of a 10-gram metal washer being held at a 1.0-meter length by a

piece of string, and having a cycle every 0.5 second? (assume the string has no mass). Hint: you will have to find out the speed of the washer. Remember it is traveling the circumference of a circle of radius 1.0 meter every 0.5 second.

3. How much force does a baseball pitcher have to exert on a 250g baseball to make it accelerate to 50 m/s2 the instant that it leaves his hand?

4. How much energy is expended (how much work is done) if that same baseball travels a distance of 30 meters?

5. If you have a light bulb that says “100 Watts,” then how much energy is it using every second? 6. While Isaac Newton developed the Law of Gravity, who was the man who discovered the

Universal Gravitational Constant, G? HEAT AND TEMPERATURE The term “therm” comes from a Greek word for heat. Dynamics is a word that means the actions that are going on. Thus, thermodynamics is the study of what’s going on with objects that are subjected to a form of energy called “heat.” A device that measures temperature is a thermometer, which means “heat measuring device.”

The thermometer was invented by Galileo, and later improved by Edmond Halley. But more on that subject later. Energy comes in quite a few varieties, and heat is one of them. One can generate heat in many ways. The most obvious is by burning, which usually produces a fire – or at least

smoke. There are two types of burning: chemical and nuclear. Chemical burning occurs when an element (atom) or compound (molecule) combines with oxygen and forms the products of carbon dioxide (CO2) and water (H2O), as discussed below. Another type of “burning” is nuclear burning and that shall be covered in Lesson 4.3. Example - The “formula” for chemical burning, as noted, could be as follows: 2C8H18 + 25O2 = 16CO2 + 18H2O + ENERGY (heat) The first group (C8H18) is the chemical formula for gasoline – the fuel that we put in our cars. The second group (O2) is the oxygen molecule. When your car engine burns gasoline, the stuff that comes out of the exhaust pipe (muffler) is the third group (CO2), or carbon dioxide, and the last group (H2O), or water vapor. The numbers in front of the groups (2, 25, 16, and 18) are the ratios of the mixture. This will be covered later in our chapters on Chemistry. Notice that one of the end products is ENERGY, in the form of heat. You may have noticed that your car engine gets hot after running a while.

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This type of reaction is a “one way” street. We can’t take water and carbon dioxide, heat them up, and create gasoline and free oxygen. The Laws of Thermodynamics will not allow this to be a reversible process. More on these laws further down.

INTERESTING BACKGROUND ON HYDROCARBON FUELS Ideally it would be wonderful if gasoline (which is one of many types of hydrocarbons) were burned efficiently, where 100% is changed into water and carbon dioxide. Unfortunately, we have never been able to make an engine that is 100% efficient, so, in reality, other junk comes out of our cars’ tail pipes, including deadly carbon monoxide (CO).

Hydrocarbon fuels that combine with oxygen to give off heat include methane (CH4), acetylene (C2H2), propane (C3H8), butane (C4H10), gasoline (C8H18 ), turpentine (C10H16), kerosenes (C12H26 to C15H32), and paraffin (C30H62). Methane is also known as “natural gas” and is used as a fuel for gas ranges and ovens in many home kitchens. Acetylene is a gas that burns very hot, and is used in welder’s torches. Propane is a gas that many campers and outdoor enthusiasts use to fuel their barbecue grills. Butane is a liquid under pressure, but a gas at room temperature. Butane burns well, and is the main component in cigar lighters. Gasoline is a liquid, of course. Turpentine is a liquid and is used to thin, or remove, paint. Kerosenes are liquids, and more of a type of fuel oil than a gasoline – albeit, thinner than oil. Sometimes kerosene is used in oil lamps. Kerosenes are also sold to homeowners who choose to heat their homes with oil. Paraffin is the stuff wax candles are made from. Many of the hydrocarbons burn very fast – explosively – like methane, propane, and gasoline. However, the heavier hydrocarbons burn much more slowly, like the paraffin in wax candles. As most people know, candles don’t explode when you light them. Well, maybe Roman Candles used in fireworks celebrations, but then, they aren’t really wax candles. Do not confuse hydrocarbons with carbohydrates. They sound similar, and their chemical formulas are similar, but while cars can “eat” hydrocarbons, humans cannot. Even so, humans can eat carbohydrates (like potatoes, etc.), but cars cannot. This is an important rule. Don’t drink gasoline, and don’t stuff potatoes down your car’s gas tank. Do not confuse gasoline with gas. A gas is any substance that expands to completely fill its container (like body odor, oxygen gas, water vapor), not gasoline! MEASURING HEAT

We humans devised a tool to measure heat and it’s called a “thermometer.” And in order to have a thermometer, we need numbers on the thermometer, which make sense. Most Americans use the Fahrenheit scale to measure temperature. A German scientist named Gabriel Fahrenheit developed this in the 1700’s. He developed this scale to go along with his new invention, the mercury thermometer. Earlier liquid thermometers used

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colored alcohol, but Fahrenheit used the liquid metal mercury. Anyway, the Fahrenheit scale is really awkward and makes little sense. Even so, we will start with it. There are some important “numbers” in Fahrenheit (F) degrees. For example, 68o F is “room temperature,” although many people feel that is still cool. We often hear that certain temperatures are “freezing,” when in reality 32o F is the temperature for the freezing of water. The boiling point of water is 212o F. Normal body temperature is 98.6o F. While we have become familiar with these numbers, they aren’t “round” numbers, nor are they based upon science. For example, what significance is 100o F? Or even 0o F? Nothing, really. Scientists use two other scales: the Celsius and Kelvin scales are used. A Swedish astronomer named Anders Celsius invented the Celsius scale, and he lived in the early 1700’s. The Kelvin scale was developed by a British scientist (originally from Ireland) named Lord William Thomson Kelvin, who lived in the late 1800’s. Another name for the Celsius scale is the Centigrade scale. This is because there are 100 equal degrees between the freezing of water (at zero Celsius) and the boiling of water (at 100 Celsius). The word “centigrade” means “one hundredth of a degree,” just like 100 cents equals one dollar. Most of the rest of the world uses Centigrade (or Celsius) for weather applications. Of course there are conversion factors from one scale to another. For example, to change Fahrenheit temperatures into Centigrade, one may use the formula below: oC = 5/9 (o F – 32o) Example If the outside air temperature were 75 F, we can change that to Centigrade like this: oC = 5/9 (75o – 32o) = 5/9 (43o) = (0.556)(43o) = 24o C (rounded) There are some nice things about using the Centigrade scale. Since “centi-“ means “hundredth” like one cent is one-hundredth of a dollar, it is easier to remember. Room temperature is 20o C; body temperature is 37o C. These numbers are more rounded than the old Fahrenheit system that most Americans have grown up with. On the other hand, if we want to measure exact energy, the Centigrade won’t work. Why? Because we need a scale in which zero degrees is exactly that – where there is nothing colder anywhere in the Universe. Scientists needed a scale that would connect energy and temperature. And that scale is the Kelvin scale. For example, 0 K is absolute zero. While we regularly use “below zero” numbers in Fahrenheit and in Celsius, there are NO degrees below absolute zero. And at 0 K, there is NO energy at all and the units are Kelvins, not degrees. For example, the internal energy of an object is E = 3/2 kT, where k is a constant, and T is the temperature in Kelvins.

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Fortunately, the size of the degree in Kelvin is the same as in Celsius, so to change from one to the other is merely an addition or a subtraction; there is nothing to multiply or divide. To change Centigrade to Kelvin, one merely adds 273: K = oC + 273o So, at 0o C (the freezing of water), the Kelvin temperature is 273. Sure, that isn’t a round number either, but we really need a scale that has the lowest temperature zero. Although scientists did invent thermometers to measure heat, we have known for more than 100 years that thermometers measure temperature, not heat. One way to measure how much heat is in hot water is to measure how long that hot water takes to melt 10 ice cubes. You know that a gallon of 80o C water will melt 10 ice cubes much faster than a quart of 80o C water. Also, the gallon will melt far more ice cubes in 5 minutes than the quart will. Obviously, the gallon of water has more heat than a quart of water at the same temperature! THERMOMETERS There are many types of thermometers. The first one was developed by Galileo and was made of glass with colored alcohol inside. A hundred years later, Edmond Halley developed a metal-expansion thermometer from a coiled band of two metals. Both of these types are still in use today. As mentioned above, Gabriel Fahrenheit created a glass thermometer about 1714, using the liquid metal, mercury. Recently mercury thermometers have been withdrawn from society due to the toxic nature of the mercury itself. When matter gets hot, it expands. If you put a fluid in an evacuated glass tube, and heat it, the liquid will expand to fill more of the tube. If you put two different kinds of metal together, and heat them, one will heat faster and expand faster than the other, thus distorting the metal band.

HEAT TRANSFER One of the ways energy is transferred is by moving heat. This is done in three ways:

1. Conduction (touch) 2. Convection (movement) 3. Radiation (heat waves)

When we touch a hot stove or hot radiator, we feel the heat immediately on our skin. The heat energy in the stove transfers directly to our body, if only locally, through our skin. This is called conduction. When we take a bath, we notice that the warmer water may be near the faucet area, so we use our hands to physically move the warmer water around, in order to make the entire bath feel about the same temperature. This physical movement is called convection. And when we stand in

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front of a bonfire, or campfire, or roaring fireplace, we can feel the heat from the radiation, or heat waves, coming off the fire. The same is true if we go to the beach on a sunny day. We feel the Sun’s heat on our skin, although we aren’t actually touching the Sun. This type of heat transfer is called radiation.

The planet Earth gets radiated by the Sun all the time. If the Earth kept all that energy and didn’t let it escape into space, the planet would burn up and even vaporize in 27 hours! Thus, there must be a balance, or type of equilibrium, where the Earth re-radiates much of that energy back out into space.

CONDUCTORS, INSULATORS, AND HEAT CAPACITY Some objects are able to transmit heat energy very well. These

are called conductors. Objects that don’t transfer heat very well are called insulators. Stone is in between a conductor and an insulator. It is sometimes called a semi-conductor. Conductors, insulators, and semi-conductors will also be brought up in Lesson 3 with electricity, so keep that in mind. Examples - Examples of conductors include most metals. Aluminum foil gets hot fast, but also cools fast. Examples of insulators include wood, fiberglass, and even air. Examples of semi-conductors include Ceramic, which is made of stone. It takes stone a long time to get hot, but when it does, it holds on to the heat and cools off slowly. Heat Capacity, also referred to as Specific Heat, is the ability of an element or compound to absorb and radiate heat energy. Examples - Aluminum has a low Heat Capacity, which means it can absorb heat very fast, and can also lose it very fast. Sitting on a metal car on a hot summer day will convince you that metal gets very hot in a hurry. But that same car in winter would be extremely cold to sit on. Wood has a high heat capacity – it is far better as an insulator. Thus, we have log cabins in the woods, to hold any heat generated inside. While wood can burn, it doesn’t absorb heat very fast at all. Key Terms and Concepts • chemical burning • hydrocarbons • types of thermometers • temperature scales of Fahrenheit, Celsius, Kelvin • Heat Transfer: Conduction, Convection, Radiation • Heat Capacity: Conductors, Insulators, Semi-Conductors • Efficiency of burning • Conversion Factors for Fahrenheit to Celsius and back

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Problems 1. Convert 80o F into Celsius. 2. Assuming that you could burn propane 100% efficiently, what would the end products be? 3. If you are cold, which method is the fastest way to get warm, and why? Conduction, Convection,

or Radiation? 4. Does the Sun heat the Earth by Conduction, Convection, or Radiation? 5. Which has a higher heat capacity – copper or styrofoam? Why? 6. Explain the difference between hydrocarbons and carbohydrates. WAVES – LIGHT, AND SOUND (During this lesson, do Lab 5: Speed of Sound) The previous lesson discussed forms of energy. Well, energy may be transferred in waves, which can come in packets of light, or packets of sound, or both. Let’s first talk about what a “wave” is. Imagine going to the beach, and watching the water come in, and go out. Each “packet” of water is called a wave. And perhaps one wave comes to shore every 10 seconds or so. The wave is identified as having a high point, or “crest,” and a low point, or “trough.” The distance from the crest of one wave to the crest of the next wave is called the “wavelength.” In an ocean water wave, that could be 30 feet (about 10 meters).

The rate at which the waves arrive is called the “frequency.” For example, if one wave crest arrives at the shore and the next arrives 10 seconds later, and the next arrives 10 seconds after that, etc., then, every 10 seconds a wave arrives. As mentioned above, then, the frequency of the wave is one divided by the time, or 1/10 per second = one-tenth of a wave per second = 0.1 / second. This is also called 0.1 cycles per second, and some call it 0.1 Hertz, after a German scientist, Heinrich Rudolf Hertz, who studied waves in the late 19th Century.

Research has shown us that the velocity of a wave, v, is

v = λ x ν where λ stands for the wavelength (using the Greek letter, λ) and ν stands for frequency (using the Greek letter, ν).

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Examples: Let’s say that the distance from one crest to the other (the wavelength) is 3.0 meters (about 10 feet). Then one can determine the speed, or velocity, of the wave, by the relationship of Velocity = wavelength x frequency = 3.0 meters x 0.1 / second = 0.3 m/s (about 1 foot per second).

One can also consider many other kinds of waves, including “waving your hand” to say “hello” to someone. As you wave at someone, you are moving your hand back and forth (probably left and right), and each time you do that, you are completing one cycle. This takes no more than about 1.0 second in most cases, so the frequency would be one cycle per second. The length of the wave would be the distance from the left side, to the right, and back to the left side, around 60 centimeters (about 1 foot each way, or 2 feet total). Thus, one can find the “speed” of the wave, or how fast you are moving your hand, by using the above relationship:

v = λ x ν = 0.60 meter x 1.0 / second = 0.6 meter per second,

or 60 cm/sec (about 2 feet per second). Of course, it’s silly to find the speed of your hand while it’s waving, but you get the idea. Both light and sound come in “wave packets,” and each has a wavelength and a frequency. Plus, each has a speed or velocity. The speed of light, using the symbol “c” is equal to about 300,000 kilometers per second (about 186,282 miles per second). This number is a constant for all colors, all reference frames, and so forth. The different colors of light all have distinct, and different wavelengths with corresponding frequencies, but all colors of light, from gamma ray to radio wave, have the same speed. Please do not confuse radio waves with sound waves. They are quite different. For instance, radio waves (like light waves) travel through empty space at 300,000 Km/s, sound waves cannot travel through empty space. They travel through different materials at different speeds. Example - Red light has a wavelength of about 6400 Ångströms, while blue light is much shorter, with a wavelength of about 4000 Ångströms. Of course, at this point, we must ask, “what is an Ångström?” An Ångström is a unit of length named in honor of a 19th Century Scandinavian scientist named Anders Jonas Ångström. It takes 10 billion Ångströms to equal 1.0 meter! However, some scientists prefer using a different unit called a nanometer. It takes 1 billion nanometers to equal 1.0 meter, so in that sense, 1.0 nanometer = 10 Ångströms = 10 Å. So, using nanometers instead, red would be about 640 nm and blue would be about 400 nm. Astronomers use Ångströms while physicists (not physicians) use nanometers. The relationship, v = λ x ν can also be used for light waves. However, instead of a speed that can change (v), we replace it with the constant speed of light, c:

c = λ x ν

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Since the wavelengths of light are so incredibly small, it only seems to reason that the frequencies of light are extremely large. As mentioned, sound comes in wave packets, too. And sound has frequencies (sometimes called “pitch”) from very high to very low. While the speed of sound is NOT a constant, it is constant within a volume that has the same temperature and density throughout. Why? Because sound waves must travel through a medium, or in other words, sound must travel through a solid, liquid, or gas. It cannot travel through a vacuum. Most of us are used to sound traveling through air, a gas. Therefore, air is the medium. At the standard temperature and pressure (like room temperature and regular atmospheric pressure), the speed of sound, in air, is about 342 meters per second (about 1,100 feet per second). Sound travels much faster in a liquid, like water, and even faster in a solid, like steel. Example - If you were to observe a thunderstorm, you’d realize that first you see the bright bolt of lightning, then later, you hear the awesome rumbling of thunder. Since light travels so fast, you see the bolt of lightning almost instantly. However, you have to wait for the sound of the thunderbolt to reach your ears, as it travels at 342 meters per second, not at the 300 million meters per second that light does. Therefore, if you see lightning, start counting the number of seconds (use a stopwatch, or count, 1-Mississippi, 2-Mississippi, etc.) and when you hear the thunder from the lightning, multiply the number of seconds you counted by 342 meters (about 1100 feet). If you counted 5 seconds, then it would be about 1 mile away (about 5500 feet). If this time span becomes shorter, this storm is moving toward you. One good thing: if you hear the thunderclap, the lightning bolt that caused it must have missed you, because it is the lightning that can kill, not the thunder (no matter how loud or scary). Key Terms and Concepts • wavelength • frequency • velocity as a function of wavelength and frequency • speed of light • speed of sound • wave packet • crest • trough • hertz • Ångström Problems 1. Who was Heinrich Rudolf Hertz? 2. Who was Anders Ångström? 3. What is the frequency of a beam of red light whose wavelength is 6000 Ångströms? 4. What is the speed of sound at STP? (standard temperature and pressure) 5. If you see an ocean wave hit the beach every 8 seconds, what is its frequency? 6. How long is a typical radio wave, which has a frequency of 560 kilohertz?

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LESSON 3

ELECTRICITY AND MAGNETISM In this Lesson, you will begin to understand the often mysterious areas of electricity and magnetism. The Lesson includes: Electricity: current, potential, power Types of Current – D.C. and A.C. Magnetism (Lab 6: Magnetism) Electromagnetic Radiation ELECTRICITY: CURRENT, POTENTIAL, AND POWER Electricity, and the study of it, has been around forever. In ancient Greek times, people could rub against some objects, such as amber, and create static electricity. Thus was born the Greek word elektron, a type of amber. Example - If you take a balloon, blow into it to inflate it, tie it off, then rub it against your hair, it may pick up enough electrons to make it stick to a nearby wall. This is because the balloon become negative and attracts the positive particles in the wall. If you live in a very humid part of the country, this does not work very well, as the electrons are also attracted to the water particles in the humid air. However, as you have removed dried clothes from an electric clothes dryer (definitely NOT humid air) you may have noticed socks sticking to shirts (that dreaded “static cling”). When you peel the sock from the shirt and hold it near your arm, it attracts your hair. The understanding, and quantification of electricity, however, didn’t start seriously until the 18th Century. One of the best known early scientists to study it was American’s Quintessential Statesman, Benjamin Franklin. His studies in electricity – static electricity – spanned the years of approximately 1747 – 1752. During the late 1770’s and the 1780’s a French scientist named Charles Augustin de Coulomb studied electricity and magnetism. In the year 1819, a Danish scientist named Hans Christian Oersted discovered electromagnetism. (Don’t confuse him with Hans Christian Andersen, a Danish writer of fairy tales who lived about the same time).

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Essentially, electricity is all about electrons – those tiny subatomic particles with a negative charge. When a whole bunch of electrons are together on a surface, but they are not moving, this is called static electricity. When electrons begin to move, such as along a wire, it is called electric current. These terms make sense, since static means “no change” or “not moving,” while current is like the continued movement and flow of a river. Example - When you plug in an electric appliance, such as a radio, television, or lamp, and then turn it on, electrons flow into and out of the device, as a river flows into and out of a lake. There are subatomic particles called “protons.” While these subatomic particles are about 1,800 times heavier than electrons, a proton has a single positive charge. An electron has a single negative charge. They are equal and opposite. Nature is so amazing! Coulomb was able to determine that each electron, and each proton, has a distinct unit of charge. He developed the unit of charge, which was named after him, called the “coulomb.” One coulomb of charge is made up of all the charges of about 6.24 x 1018 electrons (negative charge) or 6.24 x 1018 protons (positive charge). Example - If you wanted to write out the total number of electrons in one coulomb of charge, it would be 6,240,000,000,000,000,000 electrons! Therefore, each electron has a negative charge of about 1.60 x 10-19 coulomb. Each proton has a positive charge of about 1.60 x 10-19 coulomb. The current in electrical current is measured by how many electrons pass a certain point in a second of time. This is defined to be the Ampère, and is equal to 1.0 Coulomb per second. The Ampère is named after another French scientist, André Marie Ampère, who studied this stuff, during the early 1800’s. Originally, scientists thought that the protons were moving, and thus, current became the apparent direction of the movement of protons. However, it is the electrons that are moving, not the protons. Even so, we kept the direction of the current the same. Thus, if current is moving to the left, then the electrons are really moving to the right. Yes, it’s a bit confusing, but that’s the way it is. Sometimes electrical charge has the symbol of e- . This would be the same as ( - 1.60 x 10-19 Coulomb). However, in doing problems in electricity, we use the variable, “q,” to stand for whatever charge is on the object in question. The symbol for current is the lower case “i,” and it is often written in italics.

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Coulomb figured out what the force of attraction (or repulsion) between any two charged particles was. If you remember reading about the force of gravity, in Lesson 2, this law, or relationship, is virtually identical.

Therefore, Coulomb’s law of electrical force is:

Fe = [K (q1 x q2)] / r2 Where Fe is the electrical force, in units of Newtons. The large K is called the Constant in Coulomb’s law, and is equal to the number 9.0 x 109 N-m2 / C2. (Remember the gravitational constant, G?). The “q1” stands for the charge on one of the objects – positive or negative – and “q2” stands for the charge on the other object – positive or negative. The value of “r” is how far the centers of the two objects are apart. Example - For a hydrogen atom, that would mean r = radius of the atom, which is about 0.5 Ångström, or 0.05 nanometers. In the above equation, r is squared. Thus, the whole equation is: The electrical force between any two charged bodies is equal to a constant, K, multiplied by the product of q1 and q2, and all of that is divided by the square of the distance between them. This could be a force of attraction or a force of repulsion, unlike gravity, which is always a force of attraction. For a hydrogen atom: F = (9.0 x 109 N-m2 / C2)[( - 1.60 x 10-19 C) x ( + 1.60 x 10-19 C)] / (5 x 10-11)2, which is (9.0 x 109) [(- 2.56 x 10-38)] / (2.5 x 10-21) = (9.0 x 109) [(- 1 x 10-25)] = 9.2 x 10-8 N. In Mechanics, we had a concept called “potential energy.” If we were using gravity, then it was gravitational potential energy (GPE), and was equal to

GPE = m x g x h, where “m” is the mass, “g” is the acceleration due to gravity, and “h” is the distance the object can fall. Energy is always in units of joules, or based upon joules (except in Chemistry, where they prefer using a unit called “calorie”). In Electricity, like in Mechanics, we have a concept called “potential,” and its symbol is the capital letter “V” for “volts,” named for an Italian scientist, Alessandro Volta, who studied electricity in the late 1700’s and early 1800’s. Don’t confuse the symbol, capital “V,” with the lower case “v” which often means velocity. Whereas gravitational potential energy is used in mechanics, the concept is slightly different in Electricity. We use the electrical potential energy per charge, so potential is joules per coulomb. And 1.0 Volt = 1.0 joule / coulomb. Thus, we can re-write this relationship to be

Ee = q x V

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Where “Ee“ is the electrical energy, in joules; “q” is the charge on the object in coulombs; and “V” is the potential in volts. Like in gravity, the further one moves two particles from each other, the more potential there is. Example - If two charges are near each other, their force of attraction may be large. But the potential would be small, since there is not far to go to get them together. If we separate those two particles, it will take energy, and this is energy that we are storing up, on a potential basis, to use later. Since Energy is also Force times distance in Electricity, the relationship would be:

Fe x d = [K (q1 x q2) / r] which would be in the units of Newton-meters, which, by the way, are what the units of joules are. We often hear about electrical power, symbolized by the capital letter, “P.” From Lesson 2, we recall that

P = E/t but in electricity, E = q x V. And if the electrons are moving, then we have current, i = q / t. Thus we have another relationship for Power:

P = i x V Example - To find the power of a tool that draws 20 amps of current from a 120-Volt line, one just multiplies the two:

P = 20 x 120 = 2400 watts Power is in the units of watts, so watts = amps times voltage, which is also equal to joules divided by seconds. The label of every electrical appliance lists the voltage and the wattage. You can calculate the current needed Finally, in this section, we study a concept called resistance. We find this concept in Mechanics, too, when we push against a tightly coiled spring. The strength of the spring resists our pushing on it. In electrical current, electrons travel through a conductor, usually a wire. But each material that a wire is made of has a different strength of resistance. Some metals, like copper, have very low resistance, and, thus are excellent conductors of electricity. Wood, however, has extremely high resistance, and thus, it is an excellent insulator – pretty much the same as for heat in Lesson 2.

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Examples - If you were to plug a bare wire into an electric socket and hold it, while standing barefoot in salt water, it would be the last thing that you would do. The electricity would be conducted through the wire, across your body (and your heart), and into the ground. If you were wearing rubber gloves, and / or had an insulated wire, this would not happen.

A circuit is a set of one or more conducting wires that allows electrons to flow through it. The word “circuit” comes from the same root as the word “circle.” As everyone knows, there is no beginning and no end to a circle. You start at one place, and if you keep going, you will end up back where you started. It is similar with circuits. However, there is always a starting point, which is either a battery or some other source of electromotive force, also called EMF, measured in Volts. A circle of wire with no resistance can, theoretically, have a current run through it forever, once it’s started. That’s theoretically; not ideally. The battery has voltage (or potential). There is usually a switch along

the circuit near the battery. If you “close” the switch, then electrons can flow. If you “open” the switch, electrons stop. Thus, like a light switch, “on” is a closed circuit, and “off” is an open circuit. If the conducting wire had no resistance, then one could close the circuit, then instantly remove the battery, and the electrons would flow around that electrical circuit forever, and never stop. This would be similar to the concept in Mechanics of “perpetual motion.”

Well, there are no circuits with zero resistance (although by super-cooling the conductors, resistance can drop very close to zero!). Thus, we always need a source of EMF. And there will always be some sort of resistance, labeled capital “R.”

It was determined by experiment that resistance, R, is proportional to potential, V. It was also learned that R is inversely proportional to the current, i. Thus, combining these two concepts, we try to see if the relationship below is true:

R = H (V / i)

Experiment has already told us that this relationship is true. But what would the constant, H, be? By more experiments, it was learned that H = 1, so we can drop it from the formula, and end up with: R = (V / i) = volts divided by amps. Thus, the unit of resistance, R, is volts divided by amps, and given the name of ohms. In other words, 1.0 Ohm = 1.0 Volt / 1.0 Amp. Obviously, the word “ohm” must come from the name of a scientist, right? Absolutely. His name was Georg Simon Ohm, and he was a German scientist of the early 1800’s.

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Example - One could also write the above formula in many other ways, such as:

V = i x R, and since P = i x V, then we also realize that P = i 2 x R = V2 / R, and so forth

So, what is the power in a circuit that has 10 amps of current and a resistance of 3 ohms? P = (10 x 10) x 3 = 300 Watts

Key Terms and Concepts • static electricity • electric current • potential • voltage • resistance • force • energy • power Problems 1. How many electrons are in 1.0 Coulomb of charge? 2. How much heavier is the proton compared to the electron? 3. What kind of electricity did Ben Franklin study? 4. What is the electric force of attraction between a proton and an electron? 5. If Mp = 1800 Me, what is the gravitational force of attraction between a proton and an electron? TYPES OF CURRENT – D.C. AND A.C.

Example - For example, a simple flashlight battery (say, a “C” or “D” cell) has about 1.5 Volts of potential. Larger, heavy-duty flashlights often have 6.0-volt batteries. And one’s car battery is almost always a 12.0-volt. All of these produce direct current.

At home, almost all the light switches and plugs are connected to a circuit that has 20 amperes of current available and 110 to

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120 Volts. The exceptions tend to be for the large appliances, such as an electric range, an electric clothes dryer, or central air conditioning. All of those have 40 to 50 amps available on their circuits with 220 volts. They are distinguished with a different “plug” so you can’t accidentally plug in the wrong appliance. The standards in Europe for Alternating Current are slightly different, but along the same lines. Instead of 120 Volts for wall sockets, they have 200 to 240 Volts. Alternating current, well, alternates, or switches directions back and forth, at the rate of 60 times per second. This is a frequency, as you may have noticed. More often than not, this 60 cycle/second switching is labeled 60 Hertz, or 60 Hz. In Europe they use 50 Hz current.

Alternating current in your home doesn’t come from some gigantic hidden battery buried in your back yard. Instead, the electricity comes into your home through high voltage lines from an electrical substation and connects to an electrical box (or cylinder) near your home, called a transformer. The potential of the incoming electricity may be up to 10,000 volts or more, but the transformer, which is similar to an adapter, lowers the potential to about 240 Volts. Once the 240-Volt line gets to your house, another smaller transformer changes most of it into 120 Volts. A special

separate circuit of 240 Volts is brought into the house for the large appliances. But where does the electrical substation get the 10,000 volts of electricity to transmit to your local transformer? These substations distribute the power to every local transformer in its area. And the alternating current electricity that the substations receive comes from some sort of power generator, and is perhaps 1 million volts or higher.

Power generators include nuclear power electrical generators, coal-burning electrical generators, hydro-electric (from dams on rivers) generators, wind-mill style electrical generators, and from photo-voltaic cell generators that absorb energy directly from the Sun and turn it into electricity. People can also purchase gasoline-powered generators from home center stores, and use them at home when a storm knocks out the regular power, or one can take them on camping trips. Construction crews often use them on-site when they are building edifices. They come in all shapes, sizes, and prices,

depending on if you need a simple one, or a large, high-volume unit to practically run a whole house. Recreational vehicles (campers, trailers, boats) have lights, fans, home entertainment centers, air conditioners and outlets for electric appliances. They have both kinds of circuits: - D.C. to run all of this stuff (from batteries) while moving - A.C. to run all of this stuff from electrical service to campgrounds or marinas.

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Key Terms and Concepts • direct current • alternating current • battery • power generator • substation • transformer Problems 1. A typical Tesla coil may have a potential of 10,000 volts, and yet, one can be zapped by one and

not have serious injury. On the other hand, a shock from household plug could be fatal, and it’s only 120 volts. Explain.

2. Go outside in your neighborhood and try to find as many transformers as you can. In most places, they are large, gray cylinders that are placed high on telephone poles. (And in some cities, they are a large green box at ground level). Did you find it? If so, describe it.

3. Look around your neighborhood or local area for the nearest substation. Did you find it? If so, describe it.

MAGNETISM (During this lesson, do Lab 6: Magnetism) A magnet is a metal object that attracts other metal objects. Most of the time, it’s made of iron, and it attracts other things made of iron. Steel is made of iron and carbon, so it is attracted to magnets. Many cars and appliances are made of steel, so magnets are attracted to them. So are paper clips and many other items Example - Take a magnet and wander around your house testing to see what is attracted to the magnet. Do not approach the television, computer screen, or credit cards. Save that for the lab. The properties of magnets have been known for as long as electricity – maybe longer. There are two types of magnets: permanent and electromagnetic.

Permanent magnets are further divided into natural and man-made. These magnets always have magnetic fields, and always attract metals with iron in them. Electromagnets work only when they are “turned on,” as they are really coils of wire with electricity running through them. In the photograph, very thin slivers of iron (filings) have been scattered onto a sheet of paper lying on a bar magnet.

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Example - Take a magnetic compass, and place it near any of the wires in your house when the appliance is “on.” You may want to turn on a lamp, and then while the lamp is on, put the compass next to the wire between the lamp and the plug. Observe what happens. Natural permanent magnets are found in a rock called “magnetite.” Much of magnetite is made of iron, and iron is one of the most abundant elements on Earth.

Billions of years ago, when the Earth was forming, the surface was so hot that it was really a liquid, like molten lava. As the Earth cooled, the surface began to solidify, forming the basis for the crust (the continents and the sea floor). But from the very beginning, the Earth had its own strong natural magnetic field, one that would make the needle of a magnetic compass change directions. That magnetic field is still here, with the North Pole being one end of the Earth’s magnetic field, and the South Pole being at the other end.

As the molten, iron-rich crust began to cool and become solid, the iron atoms inside the lava and magma lined up, north to south, in the same directions as the Earth’s magnetic alignment. Eventually the crust became rock solid, and the parts of the soil with iron in them became natural, permanent magnets. You can dig them out of caves and mountains, and they work just fine. One place that has a large volume of magnetite is in, aptly named, Iron County, Utah. You will find out that your magnetic compass will not work there. The largest town in Iron County is Cedar City.

Scientists in the lab can take iron, melt it into a liquid, then place it in a very strong external magnetic field (like, with an electromagnet). After the iron cools and becomes solid, then it has become a permanent, man-made magnet. These are usually the ones you see in toy stores, hobby shops, physics labs, etc. Some of these magnets are extremely powerful and strong. You can “ruin,” or de-magnetize a magnet simply by heating it up. On the other hand, electromagnets are made out of wrapping electrically conducting wire around a nail, then

closing the switch so current will flow. This will make the nail a super magnet. When you turn off the electricity, or open the circuit, the nail won’t be a magnet any more – just a nail with wires around it. Example - Interestingly, electrons are attracted by magnetic fields, too. Most traditional TV sets have an “electron gun” in the back of the set, which fires electrons at the phosphorescent

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screen, causing an image. If you take a magnet and place it up to a TV screen, you can see the distortions of the images. If you leave it there too long, you will permanently damage your TV screen. See the lab. Key Terms and Concepts • magnetism • magnetite • natural magnet • man-made magnet • permanent magnet • electromagnet Problems 1. If you take a magnet and place it near a pile of sawdust, what will happen? Why? 2. Imagine taking a magnet and putting it near a number of paper clips. What will happen? Why? 3. When you put a magnetic compass near an electrical wire, when the object is turned “on,” what

happens to the needle? Why? 4. Explain an electromagnet. ELECTROMAGNETIC RADIATION Electromagnetic radiation is a ten-syllable word for energy that always travels through empty space at 300 million meters/second. We call the visible energy light. Example Our eyes are able to detect seven distinct colors: red, orange, yellow, green, blue, indigo, and violet.

These 7 colors are called the “visible” spectrum, or the range of electromagnetic energy that can be seen by humans. Each of these colors also has a range, or spectrum. Each color blends into another color. This is also the range of electromagnetic energy that the

Sun gives off most. But the visible’s “range” is so small compared to all of electromagnetic energy, that in reality, humans are virtually blind. This means that humans are not able to see most of the electromagnetic energy spectrum, but only the small range of visible light. Example - The 7 colors of the rainbow range from about 4000 Å to 6400 Å in wavelength (or 400 nm to 640 nm) whereas all the entire electromagnetic spectrum has a range tens of thousands of nm greater.

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Among the visible colors, red is the “weakest,” with the longest wavelength and the smallest frequency. The German scientist Max Planck determined that the energy of a wave packet of light is equal to a constant multiplied by the frequency of that light:

E = h ν Where E is the energy in Joules, “h” is a constant that Planck was able to determine experimentally (and is equal to 6.6 x 10-34 Joules/Hertz = 4.136 x 10-15 electronVolt seconds), and ν is the frequency in Hertz.

In his honor, the constant, “h,” has been named Planck’s constant. So, as far as visible light is concerned, violet is the most energetic. However, what is below red and what is beyond violet? Well, those wavelengths that are longer than red, and thus, have a lower energy, are called “infrared.” This means “below red.” Stars that are cooler than the Sun give off infrared. We humans also give off infrared energy.

Example Some people have tried to make everyone believe that there are black people, white people, yellow people, and red people. While the skin’s reflectivity varies from person to person, all people give off the same frequency of infrared waves. Those with fevers may have a slightly different frequency of infrared, and dead people are the same temperature as their environment. There are no people who are “black,” although there are dark-skinned peoples. No “white” people exist, either, although albino people are close. In essence, skin color is an environmental adaptation. Another energy of electromagnetic radiation is microwave radiation, a type of energy used both for communications and for warming food.

Finally, we reach radio electromagnetic energy. Some forms of radio energy have wavelengths of more than a kilometer (more than 5/8 mile). Both television and radio stations use forms of radio energy to transmit their signals. Example A radio station on the “AM dial” with a frequency of 1200 kHz has a wavelength of 250 m. Another station, on the “FM dial,” with a frequency of 95 MHz, has a wavelength of 3.15 m. We find this using λ x ν = c = 300,000,000 m/s.

Wavelengths that are shorter than violet, and thus, have a higher frequency and higher energy, are called “ultraviolet.” This means “beyond violet.” The Sun does give off quite a bit of ultraviolet light, which results in humans getting sunburned, or getting a tan, or getting freckles or getting some kinds of skin cancer. Most stars also give off quite a bit of ultraviolet light.

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Next along the spectrum is the electromagnetic energy called “x-ray.” The German scientist Wilhelm Roentgen discovered this energy accidentally, in 1895. Medical students must take at least one course about x-ray technology, and it’s called “roentgenology.” When people need to get an x-ray for possible broken bones, or ruptured disks, or decaying teeth, they must “pose” for an x-ray photo. A few stars give off x-rays – they are usually the brightest, hottest stars, or they may be part of a star system with a mysterious star called a “black hole.” Example - The next time that you are at your doctor’s or dentist’s office, ask if you can see an image of your most recent x-rays. They can be dangerous, so don’t go out and buy an x-ray camera to take huge numbers of pictures. The most energetic of all electromagnetic energy, and with the shortest wavelengths, is called “gamma ray.” These are most dangerous. Gamma rays are given off in nuclear explosions, and they are also given off at the centers of galaxies. Even a short exposure to gamma rays will cause death in about 41 minutes.

Astronomers are scientists that study the stars. The only way that they can study the stars is by “gathering” their light, with a “light funnel,” or telescope, such as at an observatory. Then the electromagnetic energies from those stars are examined. Permanent records of the starlight are made by using special cameras. While a biologist may bring in a specimen and examine a plant or animal up close in a lab, astronomers cannot pull a star in for close observation – nor can they travel to the stars to study them, at least not yet.

Key Terms and Concepts • electromagnetic energy • electromagnetic radiation • visible spectrum of light • energy below red and beyond violet • microwaves • radio waves • x-rays • gamma rays Problems 1. How many colors are in the rainbow? 2. How many colors are there outside the rainbow? 3. What life form uses light to make food? 4. Which is the most energetic electromagnetic radiation?

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LESSON 4

NUCLEAR AND ATOMIC REACTIONS

In this Lesson, you will begin to comprehend the stunning energy involved in Nuclear Physics. The Lesson includes: Small particles – molecules, atoms, and subatomic particles Building Blocks of Elements Nuclear Energy SMALL PARTICLES – MOLECULES, ATOMS, AND SUBATOMIC PARTICLES Scientists in ancient Greece proposed the existence of a “building block particle” called atomos meaning “indivisible.” Scientists have learned that atoms are not indivisible but made of subatomic particles such as protons, electrons, neutrons, and others. The concept of having tiny particles combine in some fashion to create all things has been accepted for thousands of years. However, only in the past two hundred years has the design and function of atoms come into fruition. Elements had been identified, one at a time, as history moved along. Their exact make up initially was nothing more than educated guessing, followed by a variety of experiments and tests to confirm or deny the theories.

Atoms, like helium, are made up of two things: the nucleus, and any electrons that are, in some way, traveling around it. The nucleus essentially contains two types of particles: protons and neutrons. Hydrogen is the only atom that has no neutron in its nucleus. The first model of an atom was based on that of a star like the Sun, with planets orbiting it; or a large planet with many moons orbiting it. In this way, the nucleus, or core, is like the big heavy object in the middle, while the electrons are the much smaller, lighter objects orbiting the nucleus.

Anything smaller than the atom would be, by definition, sub-atomic. Since atoms are made of electrons, protons, and neutrons, all three are sub-atomic particles. The word “proton” comes from the Greek word proton, which means “first one.” The word “neutron” comes from the Greek word, neutron, which means “neutral one.” There are also some other quite unusual subatomic particles that will be covered later.

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Some elements (or atoms) do not combine with anything else. These are called the “Noble Gases,” and they, too, will be covered in more detail later. However, with the exception of the Noble Gas family, all atoms combine with one or more other atoms. Sometimes one atom will combine with another atom just like itself, as mentioned below. Combinations of atoms are called “molecules,” from the Latin word moles which means “little mass.” There are molecules that are simple combinations of two of the same atoms, such as hydrogen gas, which is given the symbol H2. Other atoms like that include oxygen gas, O2, nitrogen gas, N2, and so forth. More complex combinations of atoms include molecules of two or more different elements. Examples include carbon monoxide, CO; hydrogen chloride, HCl; table salt, NaCl; and even the large molecule of glucose, C6H12O6, which has six carbons, 12 hydrogens, and 6 oxygens.

Molecules are really small, and, obviously, atoms are smaller yet. Subatomic particles are so small that they can’t be seen at all. We can do experiments to prove that electrons and other subatomic particles exist, but we can’t merely shine a light on, say, an electron and ask it not to move so we can photograph it. In fact, any light that we could shine on an electron would give it a huge addition of energy, so that it would take off like a shot – close to the speed of light itself! So, we would never really know where it was

The concept of not knowing exactly where subatomic particles are is called the “uncertainty principle,” developed by a 20th Century German scientist Werner Heisenberg. Pictures of larger molecules have been computer-generated after taking repeated images, and “averaging” the photos together. Those larger molecules would include paraffin (the candle wax mentioned previously). But that is about as small as we can observe – it is at the limit of our technology.

But there exists a whole host of sub-subatomic particles – smaller than electrons or protons or neutrons, called “quarks.” In 1962, an American scientist from California Institute of Technology, Murray Gell-Mann, suggested that each electron, proton, and neutron is made up of some combination of four basic sub-subatomic particles. Since there were four of them, each one was a quarter of all of them, thus, he could have called them “quarts,” but that implied milk or orange juice, so he merely substituted a “k” for the “t” in quart, and came up with quark. Since then, two more were discovered, so now there are six quarks. By 1995, scientists were able to find valid evidence of the existence of quarks. Plus, we have found some other really tiny particles, such as bosons, mesons, pions, and many others. We are still looking for, but have not found, theoretical particles such as gravitons, phonons, and such. Gravitons would be particles of gravity that cause gravity, and phonons would be particles that would cause sound. We have, however, been able to show that a particle of light does exist, and it is called a photon.

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Didn’t we just talk about light as a wave in Lesson 2.5? Yes, we did. But the odd thing about light is that it has a dual nature. It acts as a wave and as a particle. Maybe that sounds crazy, but perhaps at the smallest level, matter is energy, and energy is matter, as the German-Swiss-American scientist, Albert Einstein, had stated in 1905. Key Terms and Concepts • atoms • molecules • protons • electrons • neutrons • quarks • nucleus Problems 1. How many electrons are in a neutral hydrogen atom? Lead atom? 2. How many neutrons are in a neutral hydrogen atom? Lead atom? 3. How many types of quarks are there? What are their “names”? 4. Who was the scientist who suggested the existence of quarks? BUILDING BLOCKS OF ELEMENTS All the elements that exist in the universe were originally built out of only one element – and that is the most abundant element in all of space: hydrogen. The first element was confirmed by Henry Cavendish in 1766. The word is from the Greek “hydro” and “genes” which means the “forming agent of water.” The first and lightest element, hydrogen, is the primary building block for all other elements. In the high temperatures and pressures of the cores of stars, hydrogen fused into one element, helium, then went on to build others. Example - All stars are made of hydrogen gas. After a while, much of that turns into helium, and then to carbon, and then to iron, and various other byproducts. Here is how it is done: 4 H = He + 2β+ + Energy where the energy is [(Δm)c2] and where 4 hydrogen atoms, through several reactions, creates one helium atom, and gives off two very small, positive particles called “beta” particles. (They are really positive electrons, if that makes sense). The reaction gives off a great deal of energy. This is actually

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the chemical formula for the creation of a hydrogen bomb. At the center of every star, the equivalent of untold numbers of hydrogen bombs are going off each second.

1. However there is one very interesting event here. The mass of 4 hydrogen atoms is greater than the mass of one helium atom. And the two beta particles are the same very low weight as electrons. So, how can we physically balance this formula, if there is some mass that “disappears”? Well, it doesn’t disappear. Instead, the missing mass is converted entirely into energy. The missing mass, or Δm, when multiplied by the square of the speed of light (c2) gives an answer in the units of Newton-meters, or Joules. Thus, stars are nuclear furnaces that create heavier elements. In the Physical Sciences we use the capital Greek letter Delta (Δ) to indicate difference or change in the amount of anything. So, missing mass is Δm. In the discussion about acceleration in Lesson 2.2, the change of velocity could have been written Δv.

Example - Our Sun is “losing” mass at the rate of about 600 million tons per second, and has been doing this for 5 billion years with little noticeable effect! And every second, matter that would weigh 600 million tons is completely converted into pure energy – in all the many forms, electromagnetic radiation. As an example, if we could “convert” 1.0 kilogram of matter (about 2 pounds) into pure energy every second, what power would that create? Let’s work it out:

E = (Δm)c2 where (Δm) = 1.0 kilogram, and c = 300,000 km/sec = 300 million m/sec. And this would then be 300 million joules/sec or 300 million watts of power = 300,000 kilowatts of power. That’s enough power to run a small city for a week! And, to a good extent, that is what we do when we use nuclear power plants.

After a while, helium begins to turn into carbon, by this reaction:

3 He = C + Energy

and much later, carbon is fused into iron:

3 C = Fe + Energy

and so forth. Key Terms and Concepts • hydrogen fusion • helium fusion • carbon fusion • stellar reactions • creation of subatomic particles

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Problems 1. Give the proton-proton reaction to create helium from hydrogen 2. How are the heavier and more complex elements made? 3. What are positrons? 4. How does matter turn into energy, using Einstein’s formula? NUCLEAR ENERGY Nuclear bombs began with the atomic bombs developed at the end of World War II. After the war, scientists looked for a way to harness this massive energy to use for peaceful means, such as providing electricity to homes and businesses. However, one can’t make a bomb go off slowly, so they searched for other elements to use. Atomic bombs, such as the hydrogen bomb, are fusion reactions. This means that they take several smaller elements and make one larger element, as mentioned in Lesson 2: 4 1H1 = 2He4 + 2β+ + E where 4 hydrogen nuclei are fused together, in a chain reaction process, to form one heavier, helium nucleus. In trying to design a nuclear energy power plant, one needs to be able to control the release of energy, over a long period of time, rather than all at once. The way to do this, they found, was through nuclear fission. This reaction, fission, is just the opposite of fusion. Instead of fusing smaller elements into larger ones, fission takes very heavy elements and splits them into smaller elements. In some cases, fission also releases a great deal of energy. Example - One popular type of fuel used in fission processes is Uranium, which is naturally occurring inside Earth. Every atom of Uranium has 92 protons, all of them in the atom’s nucleus. Like many elements, Uranium has several isotopes (different versions of the element). For example, U-235 is an atom of Uranium that has 143 neutrons in the nucleus. Another isotope, U-238, has 3 more neutrons in the nucleus. U-238 is much more abundant in nature than U-235, but it is rather easy to split the U-235 nucleus to get the energy out, and it is very difficult to split the U-238 nucleus. In the fission reaction with U-235, the nucleus is bombarded with a neutron, and the nucleus splits into two smaller elements, Barium and Krypton. It also gives off about 200 Million Electron Volts (200 MeV) that can be used peacefully to power homes and businesses. As an example, 1.0 kilogram (about 2 pounds) of U-235 can yield 18.7 million kilowatt-hours of energy.

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Example - Because the amount of U-235 on Earth is limited, scientists have found a way to use the much more abundant U-238. In this new reaction, a neutron is fired at the U-238 nucleus. Since U-238 will not split apart, it actually absorbs the neutron, making a new isotope of Uranium, called U-239. The U-239 nucleus is unstable, and will spontaneously change one of the neutrons into a proton, and it will give off a positron (a positive electron, called a beta particle), thus changing the element itself from Uranium to Neptunium. A short time later, a neutron in the nucleus of Neptunium will change into a proton and give off another positron, thus changing it to another element, Plutonium. Note that while all isotopes of Uranium have 92 protons in the nucleus, Neptunium has 93 protons and Plutonium has 94 protons. Now that we have Plutonium-239, this new end product can be split into smaller elements and give off energy, just as U-235. This type of multiple reaction sequence is called a “breeder reaction” and occurs in a more advanced type of nuclear power plant called a “breeder reactor.” While there are safety concerns in all types of nuclear reactors, technology is improving at such a rate that future problems will be all but non-existent. And the fuel supply for a U-238 to Plutonium breeder reactor is almost inexhaustible. Key Terms and Concepts • atomic fusion • atomic fission • creation of heavy elements • breeder reactor Problems 1. What is the equation for nuclear fusion to change hydrogen into helium? 2. What is the reaction for nuclear fission using Uranium to give energy? 3. How many atoms of hydrogen are needed to create 1 atom of helium? 4. Which Uranium is used to create the breeder reactor?

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LESSON 5

PHYSICAL CHEMISTRY In this Lesson, you will see the relationship between the sciences of physics and chemistry. The Lesson includes: The Elements- Periodic Table Mix’n’Match – Compounds, Mixtures, and Aggregates Chemical Change (Lab 7: Testing Chemical Changes) Chemical Formulae and Balancing Equations THE ELEMENTS - PERIODIC TABLE There are over 100 elements, from hydrogen to uranium, and beyond. While hydrogen is the most abundant element in the universe, it is certainly not on Earth in very high quantities! In fact, there is a huge abundance of iron, nitrogen, oxygen, and silicon on Earth, but very little hydrogen. As more and more elements were discovered, scientists decided to put them into some sort of table, and to look for things that the elements may have in common with each other. Eventually, the Periodic Table of Elements was created.

Although the Periodic Table had a number of scientists who contributed to aspects of it, the actual Periodic Table was developed by a scientist named Johannes Periodic – no, just kidding! The real scientist was a 19th Century Russian chemist named Dmitry Mendeleyev. He determined what is known as the “Periodic Law of Elements,” which states, “Elements show a regular pattern of properties when they are arranged according to atomic weight.” This regular pattern was called “periodicity.” Mendeleyev developed the first Periodic Table in 1869, and his second draft came out in 1871. It has been evolving ever since.

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Source: http://www.wisegorilla.com/images/chemstry/periodic_table_of_elements.jpg, 01/19/2006.

As one can see, the Periodic Table puts the elements in order, according to the number of protons that the nucleus has. The very first element, hydrogen, has only 1 proton. Uranium has 92 protons, so it is much further down. “Noble” atoms, or those elements known as the Noble Gases, have all of their electrons spaces filled. Isotopes of atoms are just different versions of the atom, having the same number of protons, but differing numbers of neutrons. The word, “iso” means “equal” or “the same” and refers to the number of protons. It is the number of protons that tells one what element it is, no matter how many electrons or neutrons it may have. Example - The lightest element, with the lowest number of protons, is the gas, hydrogen, which has only one proton. In its most common and most stable state, it also has one electron – but no neutrons. Therefore, the most common isotope of hydrogen has no neutrons. However, there is an isotope of hydrogen called “deuterium” which has one neutron, and another called “tritium” which has two neutrons. These are most rare, and when they are not involved in some nuclear reaction, they quickly decay to the common hydrogen. Water, which is a combination of hydrogen and oxygen in the form of H2O, can be made with deuterium or tritium, but then it is called “heavy water” and that term is used only among nuclear scientists. The second element, helium, is also quite rare on Earth, but it is the second most abundant element in stars, and, in fact, in the whole universe. Helium has two protons, and in its most common isotope, it has two neutrons. There is another isotope, having only one neutron, and it’s called, “light helium,” which seems funny, as helium is lighter than air already, and is used to inflate party balloons.

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The Periodic Table continues to categorize each and every element, including carbon, silicon, oxygen, sodium, copper, silver, gold, uranium, and many others. There are about 100 “natural” elements, and many more that have been created by scientists to study the nuclear process. Most of the elements fabricated by scientists decay quickly (they fall apart into lighter elements) and don’t have a long life. Isotopes and Radioactivity As mentioned, an isotope is a version of an element. There may be two or more versions, or isotopes, for an element. Typically each element has a “stable” isotope that doesn’t change over time. But there are some natural elements that break down and decay spontaneously into lighter elements. In some cases, the time it takes to do this may be seconds, or fractions of seconds; in other cases, it may take billions of years to decay. Isotopes that decay all by themselves over time are called radioactive. Example - Radioactive times are called “half lives.” This means that after a period of time has passed, its half life, there is only half of the original material remaining. Then, after another half life has passed, one-half of what was left has now decayed. Thus, after two half lives, one-fourth of the original remains. Some common radioactive elements include Radium, which decays to half its original size in just about 1,622 years. Uranium-238 takes about 4.6 billion years before an original amount decays to about half of what it was. In essence, some elements never decay completely, as too much time must pass for all of it to be gone. What makes these isotopes radioactive is not merely their breaking down into lighter elements, but the by-products that come out of their decay. It is not unusual for radioactive decay to produce positrons, neutrons, neutrinos (very small particles similar to neutrons), alpha particles (these are the nuclei of helium atoms) and other high-energy, fast-moving particles. The danger being near such radioactive materials for an extended period is that they travel right through the body, and can seriously damage cells in the body, as x-rays do. Example - Up until the mid 1960’s it was popular to buy a wristwatch with a radium dial. In this way, it would glow in the dark all the time. Unlike the modern watches which have phosphorescent paint that absorbs light, then glow in the dark for a while, radium glows all the time, and has nothing to do with outside light. The people who worked in watch factories were beginning to die of cancer and other diseases. Therefore, there are no longer any radium dial watches. As mentioned in Lesson 4.2, each element is built upon some element smaller than it, all the way back to the main building block – hydrogen. And the list of all of these items is, in fact, the Periodic Table. However, the Period Table provides much more information than just that. For example, you will find the number of protons, electrons, neutrons, and the chemical formulae for the isotopes. In many cases, you will see the atomic structure, too. Plus, you are given the mass of 1.0 mole of the element’s combined isotope average. This is often called the atomic mass unit, or AMU. For those who are unaware, the unit 1.0 mole is a large number. While the unit “1.0 dozen” is equal to the number 12, the unit 1.0 mole is equal to the number 6.02 x 1023 . That would be 6-0-2 followed by 21 more zeroes! So, for example, 1.0 mole of hydrogen would have a mass of about 1.0 gram. Also 1.0

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mole of carbon would have a mass of about 12.0 grams. These grams are written near the element’s symbol in the Periodic Table which may be found in most full-sized dictionaries. Key Terms and Concepts • mole • isotope • element • radioactivity • half life • deuterium • tritium • atomic mass unit, or AMU Problems 1. How many atoms are in a mole of Helium gas? 2. What is the AMU of Carbon? 3. What is an isotope? 4. If you started with 1000 grams of radium, how many grams would be left after 3 half-lives? 5. Who created the Periodic Table? MIX’N’MATCH – COMPOUNDS, MIXTURES, AND AGGREGATES In chemical terms, we often hear the words compound, mixture, and aggregate. Defining these terms is quite easy, actually. A compound is a particle that has two or more atoms of different elements. If one has an amount of some pure compound, such as sugar or salt, that is also called a “substance.”

Mixtures are combinations of two or more separate compounds. Examples include wood, milk, concrete, and so forth. By examining them carefully, one can see the separate compounds. Milk is made of water, calcium lactate, and lipids (fats). Concrete has sand, rock, limestone, and other stuff. These are all known as “heterogeneous” mixtures. There are also “homogeneous” mixtures in which one or more of the compounds dissolves into one of the other compounds. The compound that dissolves is called the

“solute.” The compound that causes the other to dissolve is the “solvent.” An example would be salt and water. When salt is added to water, it dissolves, and the mixture becomes salt water. In this case, the salt is the solute, and water is the solvent. When the solute dissolves into the solvent, the resulting mixture is called a “solution.” Typically, it is called a solution when the particles of the solute are smaller than 10 Å (or 1.0 nm). Example - What about larger particles in an alleged solvent? Well, if the particles are say, larger than 1000 Å (100 nm) in diameter, most likely they will “settle out” and fall to the bottom, like chocolate powder in milk. Or like the ingredients in Italian salad dressing. In order to use these products, we always have to

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“shake well” before use. Particles that are too large to dissolve end up being suspended in the solvent, but eventually settle to the bottom, pulled by gravity (assuming the particles are denser than the solvent), like fine grains of sand in a glass of water. A mixture of such a solvent and such larger particles is called a “suspension,” and it’s a type of “aggregate.” There is also a middle type of mixture that is neither a solution nor a suspension. When particles are approximately between 10 Å and 1000 Å (1.0 nm and 100 nm), they don’t really dissolve, but they don’t really settle out, either. They are sort of permanently suspended, and they are given a special name, called “colloidal suspensions,” or simply a colloid. Many of the newer brands of food supplements are sold – not as pills – but as colloidal suspensions, as the body digests them much more easily. As our bodies age, it becomes more difficult for them to digest vitamins, minerals, herbs, and other pills. Thus, by grinding up the minerals into very small sizes where they are actually in a state of colloidal suspension, the body will more readily absorb them, and, thus, they will do the body more good. Examples - Fill a glass with water, and add sand. Repeat with other small items. See if they are solutions or suspensions. Key Terms and Concepts • solute • solvent • solution • colloidal suspension • aggregate • compound • mixture • heterogeneous and homogeneous Problems 1. Explain the desalination of seawater (removing salt from salt water). 2. Why do you have to “shake before using” salad dressing? 3. Is concrete heterogeneous or homogeneous? Explain. 4. What is the most efficient way to ingest minerals?

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LESSON 3

CHEMICAL CHANGE

(During this lesson, do Lab 7: Testing Chemical Change) In this section, one will learn about how things change chemically. In essence, there are three kinds of changes: physical, chemical, and nuclear.

An example of a physical change would be to take a piece of paper and tear it. Now it is no longer a large piece of paper. Now there are two smaller pieces of paper. But they are still paper. That has not changed. Example - Another example would be to take liquid water, and put it in the freezer. After a while, it will become very hard – it will turn into a solid. This new solid is called “ice.” However, it is

still water, but just in a different state. Or you can take water and put it in a pot on the stove. Bring it to boil. Eventually, all the water will be gone! But the water has not disappeared, nor become something else. It has become water vapor. It is still water, but just in a different form. All of the above deal with physical changes. In Lesson 3 of Lesson 4, we learned about nuclear changes. This occurs when we are changing one element into a completely different, such as changing hydrogen into helium, by fusing four hydrogen atoms into a new helium atom. There is no longer any hydrogen. Chemical changes occur when two or more atoms form a third substance, or perhaps several new substances. Or when one or more molecules change to form one or more new molecules. Example - An example of chemical change would be to take the paper that you tore a few paragraphs ago, and light the paper on fire with a match. As the paper burns, it changes into other stuff – water vapor, carbon dioxide, and other things. After it is all burnt up, it is no longer paper. There may be some ashes

left over, but ashes are not paper. Tearing a piece of paper won’t change that it is still paper. But burning paper will destroy whatever paper there was, and change it into one or more other things. Example - Chemical change is also true with gasoline. It has a chemical formula of C8H18, and when it is burned, or oxidized, by combining it with oxygen the formula is:

2 C8H18 + 25 O2 = 16 CO2 + 18 H2O + Energy

You do not end up with gasoline. The new substance(s) cannot behave like gasoline.

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Example - There are some reactions that are reversible, in that they can go either way. While it is not possible to take water and carbon dioxide and create gasoline and free oxygen, one can take water and reverse its process and turn it into hydrogen and oxygen by passing an electric current through the water: 2 H2O + Energy = 2H2 + O2 This process is called electrolysis. Do not confuse it with hydrox, which is a brand of cookie similar to Oreo. In summary, we have chemical change when one or more items change into other items. However, not one of the elements changes into another element. Some reactions are one-way, and some are reversible. Key Terms and Concepts • electrolysis • chemical change • physical change • nuclear change Problems 1. Give the chemical equation for electrolysis 2. Give the chemical equation for burning gasoline. 3. Give the chemical equation for fusing hydrogen into helium 4. Give the three states of water CHEMICAL FORMULAE AND BALANCING EQUATIONS If you have gotten this far, you have already come across a number of chemical equations. These are different from math or physics formulae, as they deal with the correct amounts, or ratios, of atoms or molecules on both sides of an equation. On the left side of the equation are the reactants, in other words those chemicals that will react to become something else. On the right side of the equation are the products, or those chemicals that have been created during the reaction process. Energy may be on either side. Another way to display it is:

REACTANTS ----- PRODUCTS The chemicals on the left side of the reaction arrow are called the reactants. The chemicals on the right side of the reaction arrow are called the products. Energy may be on either side of the equation, depending on if the reaction is exothermic (gives off energy in the form of heat) or endothermic (it takes energy, in the form of heat, to make the reaction work). The chemical equations must be balanced so that the number of atoms of each element on the left equals the number of atoms of each element on the right. Matter cannot disappear.

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Example - An example would be the reaction of gasoline with oxygen: C8H18 + O2 = CO2 + H2O As one can see, this equation is not balanced. Why? Well, on the left side there are 8 atoms of carbon. On the right side, there is only one atom of carbon. Even a deceased person can see that eight does not equal one! Also, there are 18 atoms of hydrogen on the left, but only 2 on the right. There are 2 atoms of oxygen on the left, and 3 on the right. Since 18 does not equal 2, and 3 does not equal 2, we must “manipulate” the formula so we have the same numbers of both on each side. HINT: manipulate any “free agents” available at the end of your chemical balancing. See that the oxygen molecule, O2, is not combined with anything else on the left side, so you would do that one last. First, we see that 8 carbons are on the left, but only one is on the right, so let’s multiply the CO2 molecule by 8, and this will then result in: C8H18 + O2 = 8 CO2 + H2O Is it balanced now? No. While there are 8 carbons on the left, and 8 carbons on the right, there are still 18 hydrogens on the left, and only 2 on the right. So, let’s multiply water, H2O, by 9, which will result in: C8H18 + O2 = 8 CO2 + 9 H2O This gives us 8 carbons on both sides, and 18 hydrogens on both sides. But is it balanced? Not yet. Why? Because there are 2 oxygens on the left, and 25 on the right. So, to balance the equation, we need to multiply the oxygen molecule on the left, O2 , by 12 ½ : C8H18 + (12 ½) O2 = 8 CO2 + 9 H2O Now, is it balanced? Yes, but we usually don’t have fractional molecules or fractional atoms. So, instead of having the number 12 ½, we choose to multiply the entire chemical equation by 2: 2 C8H18 + 25 O2 = 16 CO2 + 18 H2O Now, is everything done? Almost. We need to add the energy output of the burning of gasoline: 2 C8H18 + 25 O2 = 16 CO2 + 18 H2O + Energy Key Terms and Concepts • reactant • product • exothermic • endothermic • balanced equation

Problems 1. Balance the equation CH4 + O2 = CO2 + H2O 2. Complete, and balance, the equation C3H8 + O2 = 3. In the burning of gasoline, what are the

products? 4. Are any atoms changed into other atoms?

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LESSON 6

ORGANIC CHEMISTRY In this Lesson, you will see how the element carbon is so valuable in all of chemistry. The Lesson includes: Lesson 1: The Element Carbon Lesson 2: Hydrocarbons Lesson 3: Carbohydrates Lesson 4: Biochemistry THE ELEMENT CARBON Carbon is just about the most important element in the universe. The study of carbon and its association with life is called “organic chemistry,” as life forms have one, or more, organs.

Yes, of course, oxygen, hydrogen, and others are also critical. But try to realize that the chemistry of all life on Earth is the same, and it is because of carbon. In fact, it is most likely that any and all life forms anywhere in the universe and in the multiverse are carbon-based! For whatever reason, carbon is the only element that can combine, virtually indefinitely, with itself, to make very long chains and to make very large complex molecules. For life to exist, large, complex molecules are necessary. Coal, a common source of fuel, is mostly carbon. But if coal is heated under pressure, given enough time, it will

form diamonds, as a diamond is pure crystalline carbon. And who would want to burn diamonds? The formation process for natural diamonds is very complex, as before it was a diamond, it was coal. We know that coal is made out of what used to be plants – plants that were buried in Earth’s soil – some as long as 290 million years in the past. Long, long ago there were tropical swamps in parts of Earth that are no longer there. Green vegetation flourished in these murky areas. Generations of these plants died and then settled to the bottom of whatever swamp that they were in. Over a long period of time the organic stuff released their gases of oxygen and hydrogen. The remaining material was mostly carbon.

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In this long process, many layers of mud and sand built up, covering the rotting plant parts, squeezing and solidifying the organic material more and more. Before the decomposing vegetation turned into coal, the plant material became a dark brown, heavy organic goo known as peat. Many cultures use peat as a fuel source, as it burns when dried. However, it is low in carbon and high in moisture compared to coal. Thus, peat is not as good a fuel as coal. During more millions of years, deeper sedimentary layers over the peat exerted a great deal of heat and tremendous pressure on the stuff below. This eventually became coal. Europe (mostly of what used to be the Soviet Union) has about 44% of the coal reserves on Earth. North America (mostly the United States) has about 28%. With continued heat, pressure, and time, the coal is compressed into crystalline carbon, or diamond. Oddly enough, while less than 5% of the world’s coal is in Africa, most of the diamonds are there. Interestingly, one day back in 1866, a boy was walking along the Orange River in South Africa when he spotted a very pretty stone on the river bank. It turned out to be a 21-carat diamond. And the rush was on. A similar “rush” occurred in 1989 in northwestern Canada. It is also interesting to note that a number of meteorites – from “out there” – have had diamonds inside them. However, they are slightly different than Earth diamonds. In the Periodic Table, a vertical column of elements is called a “family”. Other atoms that are in the same “family” as carbon include silicon, germanium, tin, and lead. However, try as they might, scientists have never been able to repeat the chain-building characteristic of carbon. Silicon can form up to 7 bonds in a link, but then it falls apart. It was suggested in the 1960’s television series, “Star Trek,” that silicon life forms could exist. (Rocks and stone have a lot of silicon in them, in the form of silicate). In one episode, Dr. “Bones” McCoy was able to “heal” a rock creature by filling its wound with cement! The remaining members of Carbon’s family don’t even do as well as silicon. We as humans are a carbon-based life form. And so are all mammals. And all non-mammals. And all plants who are not animals at all. In fact, all life forms have the same chemical orientation, but that we shall cover later. Key Terms and Concepts • coal and diamonds • the carbon “family” • life forms • stories from fiction (Star Trek, Star Wars)

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Problems 1. Imagine that you want to get married, but cannot afford a diamond ring. Would it be a good idea to

get a ring with coal on it? Why or why not? 2. Before it becomes a diamond, what other phases must coal go through? 3. What was discovered in 1866? 4. What is the name of the fictional stone creature in Star Trek? 5. Mining for diamonds in South Africa is one way to get diamonds. What is another, “other world”

way to do it? HYDROCARBONS

By their very name, hydrocarbons seem to have hydrogen and carbon in them, and, in fact, they do. Hydrocarbons have ONLY hydrogen and carbon in them. The combinations of hydrogen and carbon seems almost endless, from methene and methane to ethene and ethane, to the most complex - paraffins (wax candle types). Hydrocarbons are the main group from which all other organic compounds come from. The hydrocarbons are classified into two major groups, open (sometimes called “open-chain,” and periodic (sometimes called cyclic). In open compounds having more than one carbon atom, the carbon atoms are attached to each other to form an open chain; the chain may carry one or more side branches.

Periodic hydrocarbons have carbon atoms that form one or more closed rings. The two major groups are subdivided according to chemical behavior into compounds that are either “saturated” or “unsaturated.” The saturated open-chain hydrocarbons form a similar group called the paraffin series (aka the alkane series). The composition of each of the members of the series corresponds to the formula CnH2n+2, where n is the number of carbon atoms in the molecule. Notice that the number of hydrogen atoms is always two more than twice the number of carbons.

Among the members of this series include methane (CH4), ethane (C2H6), propane (C3H8), and butane (C4H10). All the members of the series have the letters “–ane” in them. In addition, they are relatively unreactive, i.e., they do not react spontaneously at room temperature with such things as acids, alkalies, or oxidizers. The first four members of the series are gases at standard temperature and pressure (STP). The “intermediate” alkane members are liquids. The heavier alkanes are solid for the most part.

In the same way that plants become coal, animals become petroleum (“crude oil”). Petroleum contains a great variety of saturated hydrocarbons, and such petroleum products as gasoline, kerosene, heavy fuel oil, lubricating oils,

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petroleum jelly, and paraffin consist principally of mixtures of paraffin hydrocarbons, which range from the lighter liquids to the solids.

The unsaturated open-chain hydrocarbons include three series: alkene, diene, and alkyne. The alkene series is made up of chain hydrocarbons in which a double bond exists between two carbon atoms. The general formula for the series is CnH2n, where n is the number of carbon atoms. As in the paraffin series, the lighter ones are gases, the intermediates are liquids, and the heavy ones are solids. The alkene series compounds are more active chemically than the saturated compounds. They easily react with halogens (Cl, Br, etc.), adding atoms at the double bonds. Alkenes are not found in nature, but they are formed during distillation of complex

natural substances, such as coal, and petroleum refining. The first alkene is ethylene, C2H4. The dienes contain two double bonds between different pairs of carbon atoms in the molecule. They are related to the complex hydrocarbons in natural rubber and are important in the manufacture of synthetic rubber and plastics; important members of this series are butadiene, C4H6, and isoprene, C5H8. The alkynes contain a triple bond between two carbon atoms in the molecule. They are very active

chemically but are not found in nature. They form a series similar to the alkenes. The first and most important member of the series is acetylene, C2H2, which is used by

welders, as it burns very, very hot. The simplest of the saturated periodic hydrocarbons (1 or more closed rings) is cyclopropane, C3H6 , which is a “cycloalkanes.” The molecules of cyclopropane are made up of three carbon atoms to each of which two hydrogen atoms are attached. Cyclopropane is somewhat more reactive than the corresponding open alkane, propane, C3H8. Other cycloalkanes make up a part of ordinary gasoline.

Several unsaturated periodic hydrocarbons have the general formula C10H16, and they occur in certain fragrant natural oils that are distilled from plants. These hydrocarbons are called terpenes and include pinene (in turpentine) and limonene (in lemon and orange oils). The most important group of unsaturated periodic hydrocarbons is the “aromatics.” With the word “aroma” in it, one might think that perfume is made out of this group. Well, that is doubtful. Aromatics occur in coal tar. Although the aromatics sometimes exhibit characteristics like unsaturated hydrocarbons, their primary reactions bring about the replacement of hydrogen atoms by other kinds of atoms

or groups of atoms. The aromatic hydrocarbons include benzene, toluene, anthracene, and naphthalene. All of these smell rather “nasty” and are not recommended as after shave.

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Key Terms and Concepts • Hydrocarbon • carbohydrate • gasoline • propane Problems 1. Write the chemical combustion formula for burning of gasoline 2. Where do hydrocarbons come from? 3. Why does a candle burn slowly, while acetylene burns fast? CARBOHYDRATES

In recent times, “carbohydrate” has become a bad word. Both the Atkins Diet and the South Beach Diet discourage eating more than a small portion of carbohydrates every day. Why is that? Because our bodies use carbohydrates for energy. Proteins build our body and repair tissue. Fruits and vegetables promote a strong immune system and retard aging. However, when some foods are not used up, the body changes them into fat and stores them for later use – if ever. As a result, Americans have a diet of too many calories, especially in carbohydrates.

Whereas hydrocarbons are made up of seemingly endless chains of carbon with hydrogen, carbohydrates have an additional element in them. Although their name sounds almost identical to hydrocarbons, there are important differences.

First of all, a “hydrate” is any chemical or compound that, as a crystal, has water as an integral part of it. The verb, “to hydrate,” means to ensure that one has enough water to drink. While “hydrocarbon” would seem to indicate a substance that would be “wet carbon,” the term refers only to the hydrogen-carbon bonds. Carbohydrates are part of a very large family of compounds in which water molecules (H2O) are combined with carbon. As water has hydrogen in it, we have these molecules with carbon, hydrogen, and oxygen on various combinations.

These compounds are not merely hydrates of carbon, as the formula would seem to indicate. Rather, the chemical formula of most of these compounds may be expressed as Cm(H2O) n. In this chemical formula, the symbol, “m,” refers to some integer value, or some number of carbon atoms. The symbol, “n,” refers to the number of water molecules there are in that particular molecule.

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Example - Carbohydrates are the most abundant organic compounds found in nature. Green plants (and some bacteria) produce them by using the process known as photosynthesis, in which carbon dioxide (CO2) is taken from the air by the plants, water (H2O) is absorbed by the plants from the rains, and energy is supplied by means of the Sun, so as to yield the carbohydrates as well as all the other chemicals needed by the organisms to survive and grow: 6 CO2 + 6 H2O + Eo = C6H12O6 + 6 O2

where Eo represents the energy from the Sun. The molecule on the right, (C6H12O6), is glucose, which is carbohydrate food that the plant makes for itself. The carbohydrate group consists principally of sugar, starch, dextrin, cellulose, and glycogen, substances that constitute an important part of the human diet and that of many animals. The most basic of carbohydrates are the simple sugars, called “mono-saccharides.” These contain either an aldehyde or a ketone group (two important chemical groups). The most important simple sugar is glucose (C6H12O6).

Two mono-saccharide molecules joined together by an oxygen atom, with the elimination of a molecule of water, yield a di-saccharide, of which the most important are sucrose - also known as table sugar (C12H22011). Lactose, which is in milk, and maltose, which is found in many grains, are both types of sucrose. The simplest sugars are easy to digest and generally get into the bloodstream very quickly. Example -

If one is low on energy, one can eat a candy bar, or some other confection with sugar, and that energy is available almost immediately. One interesting fact is that our brains operate on sucrose alone. When the brain needs food, the body breaks it down into simple sugars to give the brain energy. But the effect is short lived. Shortly after you dump sugar into your body, the body reacts to make sure there

isn’t too much sucrose all at once. The body produces insulin to reduce the sugar’s effect. Thus, while one may get a short-term burst of energy, after the insulin is put into the body, a person’s blood sugar actually goes down – even lower than it was before. Thus, one must be careful about eating too much sugar, and it is good to have regular medical check ups to test one’s blood sugar. However, it has always been a favorite of college kids to eat a candy bar just before a test, so their brains have instant energy. When the test is over, the student is “beat,” and then sometimes rests. Poly-saccharides have enormous molecules made up of one type or several types of mono-saccharide units - about 10 in glycogen, for example; 25 in starch; and 100 to 200 in cellulose. The word “poly” means “many.”

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Complex carbohydrates are in grains, such as wheat, corn, and in potatoes. Within living organisms, carbohydrates serve both essential structural and energy-storage functions. Plants use starch and animals use glycogen to store energy; when the energy is needed, enzymes break down the carbohydrates – a type of protein discussed in Lesson 6.4.

Example - For athletes preparing for an extending competition (like running a marathon, or very active players, like in basketball and football), it is best for them to eat some complex carbohydrates a day or two before their events. It takes the body a long time to digest these, but the slow digestion doesn’t always cause swings in blood sugar. Instead, the athlete is storing up energy to use over the next few days, which will allow him to have good endurance. Key Terms and Concepts • hydrocarbon • carbohydrate • hydrates • glucose • sucrose • lactose • starch • glycogen • photosynthesis • simple carbohydrates • mono-saccharides • complex carbohydrates • poly-saccharides Problems 1. Compare and contrast carbohydrates and hydrocarbons. 2. What are hydrates? 3. What is the simplest sugar? 4. How do plants make food? 5. Why can’t humans make food as plants do? 6. Which is better for a short term “boost in energy,” and which is better for long-term endurance? A

simple sugar or a complex carbohydrate? Why?

BIOCHEMISTRY All medical professionals need to have a strong background in the field of biochemistry. In fact, biochemistry is the chemistry of life. In a way, it is a blend of chemistry and biology. However, one doesn’t need to study biology to understand chemistry, although it’s helpful. On the other hand, one cannot study biology without understanding chemistry. Life is made up of complex molecules in just the right

ratio. There are over a billion cells in a typical human being, and each cell is a chemical factory.

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As mentioned in Lesson 6, the chemistry of all life on Earth is identical. The biology may be quite different, but the chemistry is the same. Any carbon atom in any complex molecule that works in a human will work just fine in a pig, a cow, a rose, or an oak tree.

Biochemistry is the science that examines the chemicals that reside in organic life forms. As part of that, the chemical reactions in the processes of life are studied. The most important part of biochemistry is to comprehend the architecture of biological molecules, and how they act. Carbon-containing compounds that are part of the live cells participate in the chemical reactions that lead to growth, energy use and storage, and reproduction.

There are a large number of biological molecules in the cell. The most important types of biological molecules include proteins, carbohydrates, nucleic acids, and lipids.

AMINO ACIDS Proteins are large molecules made up of amino acids. A cell may use just 20 amino acids to build thousands of different proteins. Amazingly, each amino acid has its own specific task to do. The most interesting proteins are the ones that do the most work. They are called “enzymes.” Enzymes act as catalysts to speed up the cellular chemical reactions. ENZYMES Enzymes are very useful household products in daily life, as

they can be used with household detergents to remove many stains in clothes. While bleach also removes stains (household bleach is made of sodium hypochlorite), bleach cannot remove protein stains. Only enzymes will break down the proteins in the stains and remove them. Body fluids of animals contain a lot of protein, and can stain cloth easily. As we learned in Lesson 6, carbohydrates are used as a fuel to run the cell – very much like hydrocarbons are used as fuels to run automobiles. The elements of carbon, hydrogen, and oxygen that they contain are in equal proportions. Most plants use photosynthesis to make carbohydrates from carbon dioxide, water, and the Sun’s energy. Animals, however, obtain their energy from eating plants – and other animals in some cases – to get the carbohydrates that they need. NUCLEIC ACIDS “Nucleic” acids sound as if they are acids in the nucleus of atoms. They aren’t. Instead, it is their job to store and transmit the genetic code within cells. Nucleic acids are large molecules that provide information to all material in the cell. Example -

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Ribonucleic Acid and Deoxyribonucleic Acid carry the genetic map, or blueprint, for life. Sometimes they are referred to as RNA and DNA. Their exact and complicated patterns were first discovered and explained by British physicist, Francis Crick, and American chemist, James Watson, in 1953. DNA is the genetic stuff of all organisms with cells – and viruses, too! DNA is like a computer that has all the information required to create proteins and to allow cells to reproduce themselves. DNA is able to copy itself for each new cell or virus to use, passing on the necessary information. In most organisms, DNA is organized on chromosomes, which are inside the nucleus of the cell. It is like the DNA downloads and copies the data, and hands it to any new cell that is split off from the original.

DNA is a two-chain molecule, with each chain made up of a whole host of chemicals called nucleotides, linked together. The model of a DNA molecule looks like two spiral staircases, coming down from some upstairs location. Mathematically, it is known as a double helix. Each nucleotide has three parts: a sugar, a phosphate, and a “base.” The sugar molecule is called deoxyribose, and it has a pentagon shape, with a chemical formula of C5H10O4.

The phosphate group, contains the radical PO4, and as an acid would be H3PO4, or phosphoric acid. There are four “bases,” each of which contains nitrogen compounds. These four bases are adenine (symbolized by an “A”), guanine (“G”), thymine (“T”), and cytosine (“C”). Adenine has a chemical formula of C5H5N5. Guanine has the formula C5H5ON5. Thymine is C5H6N2O2. And finally, cytosine is C4H5ON3. As one can see, each base has 4 or 5 carbon atoms, 5 or 6 hydrogen atoms, and 2 to 5 nitrogen atoms. Only one, Adenine, has no oxygen, while the others have 1 or 2 oxygen atoms. The deoxyribose molecule is in the middle of the nucleotide with a phosphate group on one side and a base on the other. The phosphate group of each nucleotide is also connected to the deoxyribose of the nucleotide “next door” in the chain. These linked deoxyribose-phosphate gangs form the parallel sides of the twisted staircase. The bases face inward toward each other, forming the steps of the staircase. Damaged portions of genetic DNA lead to various diseases. In addition, scientists have now learned how to clone, or duplicate exactly, any mammal, including humans. It’s almost what the Greek gods

were able to do, when Athena sprung spontaneously out of the head of Zeus! Example - In recent years, a weight-loss technique called “liposuction” has become popular. What the medical professionals are doing is that they are suctioning out, or removing, deposits of “lipo-stuff” from the body. This

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lipo-stuff has a scientific name: “lipids.” They are essentially fat. Even so, they do play a role within the cell. Some are stored for use as fuel; other lipids become part of the cell membrane (the cell’s wall).Biological molecules of many other types are also found in cells. When we breathe in oxygen our bodies use this oxygen in chemical reactions. The results include “free radicals” as by-products.

FREE RADICALS Free radicals are complex molecules that have atoms in them with one “empty space” for an electron. A free electron makes the free radicals very reactive, always searching for another molecule to share, or steal, its electron. Free radicals then roam throughout the body and cause damage to cells by stealing stable electrons from within other cells, which then causes more free radicals, more instability, and more cell destruction.

This cell damage can really hurt our body’s ability to fight disease. In fact, studies have shown that this damage is connected to every part of the body’s aging. In essence, the cells and their molecules are being “oxidized,” or burned up. Thus, it is necessary to find something that will “put out the fire,” or, in other words, something that is the opposite of oxidizing. Biochemists call them “antioxidants.” Antioxidants protect against this oxidation reaction in cells by rendering free radicals harmless – making sure that cellular molecules are not attacked for their electrons.

Our bodies naturally produce some antioxidants, but most must be eaten. Fruits and vegetables have the largest number of natural antioxidants – particularly broccoli and blueberries. However, most people don’t eat enough fruits and vegetables, so taking food supplements may be a good idea. Free radicals, as a result of their collective cellular damage, contribute to aging, and thus, ultimately to death. Theoretically, if we can find a way to limit, or remove, free radicals, humans could live forever. Unless they died in an accident, a war, or in some other tragedy. Key Concepts • Biochemistry • RNA and DNA • nucleic acids • bases • Crick & Watson • Double helix

• Antioxidants • Free radicals • Amino acids • Proteins • Enzymes

Problems 1. Define the term “biochemistry” 2. What is the difference between RNA and DNA? 3. What are nucleic acids? 4. What are the four “bases”? 5. Who are Crick and Watson? 6. What is the shape of DNA? 7. Explain a free radical and an antioxidant 8. What special property do enzymes, which are proteins, have?

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LESSON 7

UNIFIED FIELD THEORY

In this Lesson, you will become familiar with the other physical sciences, including, but not limited to: astronomy, geology, and meteorology This Lesson includes: Astronomy (Lab 8: Visit a Local Planetarium)

Geology (Lab 9: Hunting for Rocks)

Meteorology (Lab 10: Weather)

Unified Field Theory and Other related sciences

ASTRONOMY (During this lesson do, if you can, Lab 8: Visit a Local Planetarium - Optional) Astronomy is among the oldest of the sciences. In reality, it is the branch of physics known as “astrophysics.” A story is told that during his first night on Earth, the first man, Adam, walked out of his cave, looked up at the stars, and said something like, “Ohwhadeen glop! Restarriffin lokdugan!” or whatever language he used, which loosely translated means, “Wow! Look at all those stars!” Thus, making Adam the first astronomer. In Aramaic, the word “Adam” means “first man,” so whoever the first man was, anthropologically or religiously, he was called “Adam.” Some people believe that Adam was born or created 6,000 years ago. Maybe that number was a typographical error, and that the real time was 6,000,000 years ago. Throughout the ages astronomers have tried to count the stars, name the stars, make patterns out of stars, and study the energy (light) coming from the stars. But really, astronomy has two branches: stellar astronomy (stars, galaxies, nebulae), and planetary astronomy (moons, planets, comets, asteroids, comets).

In the old days, everything in the sky was a “star,” so that is how we got the words “planet” (from the Greek planetes asteros, or wandering stars), “comet” (cometes asteros, or hairy star), and “asteroid” (asteros, or star-like object), even though these objects are not stars at all. Modern astronomy is now broken down into astrophysics (which used to be called stellar astronomy) and geophysics (which used to be called planetary

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astronomy), as physics is the main science that is used to understand and explain everything in the cosmos. And, essentially, chemistry, too, is a special branch of physics, as biology is a special branch of chemistry. PLANETARY ASTRONOMY Studying the planets and the Moon can be most interesting. After all, with a small telescope one can see the planets pretty well, and the Moon is breathtaking. Most of the mass of the Solar System is the Sun itself. But the Sun is a star, and will be discussed later. The topics of study in planetary astronomy include planets, moon, comets, meteors, and asteroids, and other things related to them. There are nine major planets, and they are, in their order from the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. To help you remember that, make up a mnemonic (word game) to assist you. For example, take the first letter of each of the planets and string them together, like this: MVEMJSUNP Of course, in and of themselves that won’t help much. But now use those letters to make new words and thus, a sentence. The sillier, the better. How about: Main Valves Explode Making Janitors Stand Under New Pipes. You get the idea. There are many such “games” to help you remember. There are two types of planets: big and little. The big ones are really just large balls of gas, and they are given the name “Jovian Planets” – for Jove, another name for Jupiter. The Jovian planets are Jupiter, Saturn, Uranus, and Neptune. The little planets are small balls of rock. They are Mercury, Venus, Earth, and Mars. The planet Pluto may be included in here, too, but some would rather call it a special name. No matter. The four inner planets are called the Terrestrial Planets, since they are like Terra, another name for Earth. Of course, Earth is an ideal place to live. Venus is too close to the Sun, and therefore, too hot. Mars is too far away, therefore too cold. Earth is “just right.” Mercury is even closer than Venus, and the Jovian worlds are in the frosty cold of outer space. Seven of the nine major planets have moons. Mercury and Venus do not have any moons. Earth has a moon called, “Moon.” Mars has two tiny moons. Jupiter, Saturn, Uranus, and Neptune all have large numbers of moon. In fact, those planets are almost like tiny solar systems. Pluto has one moon that is almost as big as Pluto itself.

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And scattered throughout the Solar System are the “leftovers”: the cosmic invaders of comets, meteors, and asteroids. Comets are mostly dirty snowballs with very long orbits. Asteroids are "wannabe planets” that never got large enough. And Meteors are just made of space dust. Comets are usually in our skies every night – although they may not be bright enough to be seen easily. Meteors fall from the sky as the Earth gets near them, and some people call them “shooting stars.” And asteroids are in various locations, including a large number of them between Mars and Jupiter. Our Moon is a lovely sight, of course. It travels around Earth in about a “moonth,” or month, and goes through various shapes, or phases. (Did you know that phase and shape have the same letters?). Sometimes the Moon covers the Sun, and that’s called a Solar Eclipse. Other times the Moon “hides” behind Earth and grows dark in Earth’s shadow. That’s a Lunar Eclipse. If you get a chance, go observe an eclipse or two. Planets, moons, comets, meteors and asteroids form as part of a star’s formation. They are made out of some of the original material that was there for the star. However, not all stars have “solar systems,” only about 20%. In brief, that’s about all there is to the Solar System. But what lies beyond? STELLAR ASTRONOMY Stars are so far away that they look like small, pinpoints of light. They are not just tiny dots, however. They are about the size of the Sun, which is our star. Our Sun is more than 300,000 times heavier than Earth, and extremely hot. The “surface” of the Sun is 6000 Kelvin (about 12,000 degrees Fahrenheit), but the center of the Sun, and any star, is millions of degrees. Hot using any scale.

Stars, just like the Sun, create their energy by nuclear reactions. At the center of all stars the gas hydrogen is turned into helium, releasing a tremendous amount of heat. Stars begin as an enormously large “blob” of gas and dust. Gravity pulls it all together, and eventually, it “ignites” into a nuclear-burning, self-sustaining star. And sometimes it has planets. More often than not, two or more stars will form out of the same blob of gas and dust. In fact, about 60% of the stars are really “multiple” star systems.

Stars are so far away that we don’t tend to measure their distances in miles or kilometers, but instead, in “light years.” As you have learned, light travels about 300,000 km/s. Since there are about 31.7 million seconds in one year, during a year’s time, light will have traveled 9.5 trillion kilometers (5.9 trillion miles). This distance is called a light year. Stars take about 1 billion years to form. Then they last a long, long time. Some live 10 billion years or more. Our Sun is 5 billion years old. When stars get older, they first expand their outer layers and become quite large, and much cooler. They are then called “Red Giants,” and they are so large, their outer layers would reach out to Jupiter – or beyond!

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About 1 million years after this, the outer layers escape into space, leaving a very small, dense, bright star called a “White Dwarf.” The size of a White Dwarf can be about the same as Earth, but 300,000 times heavier! A few stars shrink even smaller and become “Black Holes” and disappear. And that seems like “magic,” but it’s not. Some stars form in groups called clusters. These can be relatively small groups of 100 or fewer, or as many as a few million. However, once a group of more than a billion stars forms, that is what is called a galaxy. Our galaxy is called “the Milky Way.” This is because the word “galaxy” comes from the Greek word galactos which means “milky way.” Our galaxy contains about 400 billion stars, and it also has two smaller “satellite” galaxies that go around it, just like a moon orbits a planet.

In our “galaxy neighborhood” there are at least 20 galaxies. The largest in the group is called the Andromeda Galaxy. It has slightly more than our 400 billion stars, and it is at a distance of 2 million light years away. Andromeda also has two satellite galaxies going around it.

Galaxies come in different shapes and sizes, too, and they are at different distances. The “closest” galaxies are less than 2 million light years away, while the most distant are about 20 billion light years away. The most distant objects that we see are believed to be the nuclei of newly forming galaxies, and we call them Quasi-Stellar Radio Sources, or Quasars for short. Our universe, called “the Universe,” seems to be expanding, or getting larger. If it were the shape of a ball, its diameter might be 40 billion light years, or more. There are some mysteries left to solve. Such as what happens to a star once it shrinks down to the size of a pinhead, and then disappears from time and space? This is the “black hole,” and it occurs when very heavy stars collapse under the force of gravity until they, well, vanish. Do they go into another universe, or what? It is thrilling to think about. Much more can be learned by taking a course called Earth & Space Science. Key Terms and Concepts • Planet • Moon • Comet • Asteroid • Meteor • Sun • Solar System • Star • Red Giant • White Dwarf

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• Black Hole • Cluster of Stars • Galaxy • Quasar Problems 1. What is the difference between a planet and a star? 2. What is the difference between a planet and a moon? 3. What is a comet? Meteor? Asteroid? 4. How many planets are in the Solar System? Their names? 5. What is the name of our galaxy? 6. How many stars are in our galaxy? 7. What is the name of a star that shrinks until it vanishes? 8. What is the name of the galaxy-like nucleus at the edge of the universe? GEOLOGY (During the lesson, do Lab 9: Hunting for Rocks) Geology is the science of Earth. The word geo is an ancient word for Earth, and logos means “the study of.” Thus, geology is the study of Earth. The science of geology is really a branch of physics called “geophysics.”

More specifically, geology is the study of what makes up the solid Earth, essentially from the surface to the core. As a result, mountains, valleys, hills, craters, volcanoes, glaciers, lava, rocks, and minerals are all part of geology. Geography is a branch of geology, specifically dealing with Earth’s surface. Cartography, which is part of geography, is the study of map-making.

Example - For great adventurers and explorers, a good map is a must. The famous discoverer, Christopher Columbus, was not only a sailor, but also a mapmaker. THE EARTH’S SURFACE On Earth, there is a cycle that rocks pass through called the GeoChemical Rock Cycle. In this cycle, hot, molten material beneath Earth (called magma) is belched out by volcanoes and as soon as it hits the air, becomes lava. Some of the lava cools and becomes hard. This is now called an “igneous” rock. Some of these igneous rocks get washed away, and joins with other rocks. This is called a “sedimentary” rock, such as limestone. Other rocks combine, and under pressure, form a dense, heavy rock known as a metamorphic rock, such as some granites. Then, over a long time, a few metamorphic rocks get heated under pressure, melt, and re-join the hot, molten material (magma) beneath Earth’s surface again. Thus goes the cycle.

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Source: http://yates.nn.k12.va.us/images/rocks.gif, 01/19/2006.

THE INSIDE OF THE EARTH Earth has several spherical layers, or levels, beneath the surface. The top 50 kilometers (30 miles) or so is a very thin layer called the “crust.” Below that is the “mantle.” The upper mantle and the crust is where all earthquakes come from. The lower mantle is very warm and quite soft. Example - The study of Earthquakes is called “seismology.” The Earth’s crustal surface is divided into sections called “plates.” These plates “float” on the layer below them – the mantle. These plates are not locked down, and they do move relative to each other. When the plates move quickly, an earthquake occurs. Sometimes earthquakes occur between two landmasses, such as those in California over the past 30 years. Some occur between two parts of the crust that are on the ocean floor. The one on December 26, 2004 generated huge waves of water called “tsunamis” which caused great death and destruction along coastal areas in such places as Thailand, Indonesia, Sri Lanka, and nearby areas. Tsunamis are also sometimes called “tidal waves,” although they have nothing to do with tides.

Inner Core solid Outer Core

Lower Mantle Soft

Crust Solid

Upper Mantle

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The three most active earthquake areas in the world include Turkey, Chile, and Southern California. However, earthquakes can occur almost anywhere. Below the mantle is the outer core, which is liquid nickel-iron. Finally at the very core, no matter that it’s 3000 Kelvin or more, the pressure is so high that it is solid nickel-iron. Example -

In the Jules Verne book, Journey to the Center of the Earth, a group of explorers are able to “climb down” to the Earth’s very center. While there, they find a large ocean of water. That scenario, however, is just fantasy. In reality, we have a large core of rock-solid nickel-iron. The rotation of the outer liquid core helps create the Earth’s magnetic field. A magnetic compass can help one find the directions of north, south, east, and west. The Earth’s insides are similar to those of other planets, too. For more information on this, one can take a course in Earth & Space Science.

KEY TERMS AND CONCEPTS • “Geology” • Geography • Cartography • GeoChemical Rock Cycle • Igneous, Sedimentary, Metamorphic • Crust • Mantle • Earthquakes • Seismology • Tsunami • Inner and Outer Core • Earth’s Magnetic Field Problems 1. What does the word “geology” mean? 2. Who was a mapmaker and famous discoverer? 3. Explain the GeoChemical Rock Cycle 4. Describe the layers of the Earth’s insides 5. What is a tsunami? 6. What three regions of Earth have the greatest earthquake activity? 7. What causes the Earth’s magnetic field?

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METEOROLOG (During the lesson, do Lab 10: Weather)

Meteorology sounds like one may be studying meteors or rocks that fall from outer space. That is not true. The word Greek word meteor means “high in the sky,” and thus, those who study the weather and the climate are really studying what is going on in the sky overhead – the air that is “high in the sky.” A person who studies the weather is a meteorologist. The science of meteorology is really the branch of physics called “atmospheric physics.”

Example - Well, then, what do we call a person who studies those rocky meteorites from outer space? A meteoriticist!

Meteorology is a science that is nothing more than atmospheric physics. In studying the Earth’s air, also known as the Earth’s atmosphere, scientists realize that the air is thickest, or heaviest, at the bottom. The air that is way up in the sky is thin, such as the air at the top of a mountain. Anyone who lives near the ocean, but vacations in the mountains, immediately notices a lack of enough oxygen when they go up high – causing them to gasp for breath.

The Earth’s atmosphere has six lower levels. The lowest level of Earth’s atmosphere, which is about 8 to 11 kilometers up (5 to 7 miles) is called the “troposphere.” The Latin word tropo means “to change” or “to turn,” and, in fact, it has the same root as the word “tropic.” The word “sphere” means a ball. The troposphere is where we live. The air is most turbulent here.

Above the troposphere is the mesosphere (meso means “middle”), and the two are separated by a boundary called the “tropopause” (“pause” means “to stop.”) The lowest level of the mesosphere is often called the “stratosphere,” for that is where the “jet stream” is and where commercial airline jets fly. The word “stratos” comes from the Latin stratus, meaning “to spread out.” Above the mesosphere is the ionosphere (from “ion,” a charged particle), where the air is extremely thin. However, the few atoms that

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are in the ionosphere get turned into ions (they lose electrons) when the strong solar rays hit them. The boundary between the mesosphere and ionosphere is called the “mesopause.” Finally, the most outer part of Earth’s air is the exosphere (exo means “away” or “out from,”) meaning the most far away sphere of air. It is virtually a perfect vacuum out there. Weather changes occur due to the Sun’s heat combined with the Earth’s rotation. Local conditions, such as mountains and nearness to water also affect weather. CLOUDS

Clouds are an important part of weather. Most people think clouds are made of water vapor. However, water vapor is invisible. Clouds are made up tiny water droplets, and they are constantly changing. You will never see the same cloud twice, even if you look away for one second. You may see different types of clouds twice, but not the exact same cloud. And different types of clouds exist at different levels.

The Main Types of Clouds Are: 1. High – Cirrus family (Cirrus, Cirrostratus, Cirrocumulus) 2. Middle – Alto family (Altostratus, Altocumulus) 3. Low – Stratus family (Stratus, Stratocumulus, Nimbostratus) 4. Vertical – Cumulus family (Cumulus, Cumulonimbus) Nimbus is Latin for “cloud.” The vertical clouds often lead to heavy summer thunderstorms. And sometimes there are very heavy desert thunderstorms, but the rain drops evaporate before they ever reach the ground! CLIMATE Climate (from the Greek klima, meaning the angle of the Sun) is the average type of weather in a certain location, over a period of many years. It would be okay to say, “The weather today will be….” but it would be silly to say, “The climate today will be…” as the climate in any one place is the same for many centuries. Examples - Climatic regions can be classified in a number of ways. However, for this textbook, we shall use only two: by temperature and by precipitation.

THERE ARE FIVE CLIMATE ZONES BASED UPON TEMPERATURE: 1. Tropical (averages above 20° C or 68° F all year). Examples are the tropics, such as the Caribbean. 2. Subtropical (averages above 20° C at least 4 months and the rest no colder than 10° C). Examples

include states like Georgia and Alabama. 3. Temperate (4 - 12 months at 10° - 20° C). States like Missouri and Illinois. 4. Cold (at least 1 month at 10° - 20° C, and the rest cooler). Canada is an Example. 5. Polar (averages are below 10° C all year). Northern Alaska.

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There are eight climate zones based upon precipitation (rain or snow): 1. Equatorial (rain all year). Examples would include the Amazon. 2. Tropical (rainy summers and dry winters). South Florida. 3. Semiarid Tropical (dry most of the year, with some summer rain). Parts of Texas and New Mexico. 4. Arid (dry all year). Las Vegas 5. Dry Mediterranean (dry most of the year, but some winter rain). Los Angeles 6. Mediterranean (dry summers and rainy winters). Nice, Rome, Athens 7. Temperate (rain all year – but not as much as Equatorial). Missouri. 8. Polar (little rain or snow all year). Pt. Barrow, Alaska; Novosibirsk, Russia. The one city in the United States with the “best” all-around weather is San Diego, California. It is about 75 F every day and about 55 F every night all year round, with many sunny days and not much rain. Yuma, Arizona, is the “sunniest” city, with 360 days of sunshine per year. The Southeast is very warm and very humid in the summer. The Southwest is very hot and very dry in the summer. The Northern Plains and Northern New England are bitterly cold in the winter. And there are many other examples. Consult your local newspaper or news & weather station for daily and yearly temperatures and precipitation. Key Terms and Concepts • meteorology • meteorites • troposphere, mesosphere, ionosphere, exosphere and all other atmospheric levels • clouds and their various types • precipitation • climate • climatic regions Problems 1. What is the job title of a person who studies meteorology? 2. What is the job title of a person who studies meteorites? 3. Name the six lowest levels of Earth’s atmosphere. 4. There are 4 main cloud types. Name them. 5. Climate can be classified as a function of what two items? List the subcategories of climate regions

for each of these two. UNIFIED FIELD THEORY AND OTHER RELATED SCIENCES One could find almost an infinite number of sciences, as over time, we have diversified the study of just about everything. Which means that knowledge is really holistic. Holistic means “one great whole.” One cannot separate knowledge from other knowledge. To this end, some modern physics researchers are trying to “tie it all together.” If we could do it, that would be called the Unified Field Theory.

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FIELD THEORY In order to understand this last part, one must understand the concept of “field.” In essence, it tells you the value of whatever you are looking for anywhere in that field. Example - Oh, sure, you may be aware of a cornfield or a soccer field, but what about a field in science? Let’s start with a cornfield. Really. Anywhere that you stand in that cornfield, there is a value, that is, a certain number of healthy ears of corn, or at least corn stalks. Okay, how about soccer? Well, the value of the game is where the soccer ball is on that field. At any place on the field, that ball has a certain value. Near the mid-way point, it may not be very important, but the value goes way up as it approaches the goal. And it’s worth a lot in the goal. Example - Now, let’s talk about a temperature field. Imagine standing in a one-room house on a cold winter’s day up north. There is a fireplace in that house, with a nice fire going on. If you take a thermometer and pick 10 places at random all over that house, you will find 10 different temperatures. In other words, wherever you are, there is a value. A place on the floor far from the fire is probable very cold. A point on the ceiling above the fireplace is probably very warm. As you wander around the room, the temperature values change. In fact, you head will feel warmer than your feet, as heat rises.

So, the Unified Field Theory would be one theory, or law, that would bring all the laws and values in all fields together in one explanation. Yes, it sounds difficult. That’s because it is. About 60 Years ago, a British scientist named James Maxwell developed a series of four essential equations from which all other physics equations evolve. Recently, we’ve tied 3 of those four together. Now the trick is to get that 4th equation somehow linked to the other three.

Example - If it can be done to tie all four together, then there will be one, and only one equation that everything else comes from. It’s like finding the one and only common ancestor for humans and apes. Or finding the one and only true god. Maxwell’s four equations are well known among scientists all over the world. It isn’t very important to know their mathematical formulae – one would have to understand the mathematics of calculus to appreciate Maxwell’s formulae. However, the four laws are listed below, with a brief explanation, or “translation,” that may make them more understandable. 1. The closed loop integral of an electric field is equal and opposite to the change of the magnetic

field through that area enclosed. Translation: A magnetic field that changes over time generates an electrical field. Example: electrical fields are similar to gravity fields. So, if you were to keep changing a magnetic field (using an electromagnet, or even by throwing a magnet), then an electric field would exist.

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2. The closed loop integral of a magnetic field is equal to the change of the electrical field through that area enclosed. Translation: an electrical field that changes over time generates a magnetic field. Example: if you place a magnetic compass near an electrical cord that is plugged into a wall socket, the compass needle will move (if the appliance is turned on), since the current in the cord (the moving electrons) is making a magnetic field.

3. The closed loop integral of an electric field over the enclosed area equals the charge moved, divided by the universal constant of permittivity, �0. Translation: the movement of an electrical field is a function of how much electric charge is traveling through. In reality, this means if current is flowing, then the value of the strength of the electrical field can be found out.

4. The closed loop integral of a magnetic field over the enclosed area is equal to zero. Translation: A magnetic field is not created by some mysterious magnetic particle, nor can it be stored. It goes in and comes out, leaving nothing behind. Example: you throw a magnet through a metal hoop. As it approaches the hoop, a magnetic field is created (and an electric field), but as it passes through and leaves the hoop, no magnetic field is left behind.

In any event, the one and only equation for everything is called the Unified Field Theory. And, well, maybe someday it will be discovered. It is your job to keep your eyes and ears open – or better yet – discover it yourself! In conclusion, we have covered the areas of physics and chemistry, with a number of other related physical sciences as well. However, physical science is only one of the Natural Sciences. The others include the Life Sciences. And beyond that, we have Social Sciences and Behavioral Sciences. In essence, science is just the study of everything. Key Terms and Concepts • Unified • Field Theory • Corn Field • Temperature Field • Maxwell’s 4 Equations • Other sciences Problems 1. Explain a field. 2. How many laws did Maxwell develop? Briefly, in your own words, explain them. 3. What is the Unified Field Theory? 4. Why is this theory called “Unified”? 5. Why is it called a “theory”?

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COURSE OBJECTIVES

The purpose of this course is to provide opportunities to study the concepts of matter, energy, and forces, and their applications through exploratory investigations and activities. The student will:

• Know that investigations are conducted to explore new phenomena, to check on previous results, test how well a theory predicts, and to compare different theories.

• Know that from time to time, major shifts occur in the scientific view of how the world works, but the more often, the changes that take place in the body of scientific knowledge are small modification of prior knowledge.

• Understand that no matter how well one theory fits observations, a new theory might fit them as well or better, or might fit a wider range of observations, because in science, the testing, revising and occasional discarding of theories, new and old, never ends, and leads to an increasingly better understanding of how things work in the world, but not to absolute truth.

• Know that scientists in any one research group tend to see things alike that therefore scientific teams are expected to seek out the possible courses of bias in their design of their investigations and in their data analysis.

• Understand that new ideas in science are limited by the contest with which they are conceived, are often rejected by the scientific establishment, sometimes spring from unexpected findings and usually grow slowly to form many contributors.

• Understand that in the short run, new ideas that do not mesh well with mainstream ideas in science often encounter vigorous criticism and that in the long run, theories are judged by how they fit with other theories, the range of observations they explain, how well they explain observations and how effective they are in predicting new findings.

• Understand the importance of a sense of responsibility, a commitment to peer review, truthful reporting of the methods and outcomes of investigations and making the public aware of the findings.

• Know that scientists assume that the universe is a vast system in which basic rules exist that may range from very simple to the extremely complex but that scientists operate on the belief that the rules can be discovered by careful, systematic study.

• Know that scientists control conditions in order to obtain evidence, but when that is not possible, for practical or ethical reasons, they try to observe a wide range of natural occurrences to discern patterns.

• Know that performance testing is often conducted using small-scale models, computer simulations, or analogous systems to reduce the chance of system failure.

• Know that the number and configuration of electrons will equal the number of protons in an electrically neutral atom and when an atom gains or loses electrons, the charge is unbalanced.

• Know that a number of elements have heavier, unstable nuclei and decay, spontaneously giving off smaller particles and waves that result in a small loss of mass and release a large amount of energy.

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• Know that elements are arranged into groups and families based on similarity in electron structure and that their physical and chemical properties can be predicated.

• Know that the vast diversity of the properties of materials is primarily due to variations in the forces that hold molecules together.

• Know that a change from one phase of matter to another involves a gain or loss of energy.

• Know the difference between an element, a molecule and a compound.

• Understand that matter may act as a wave, a particle or something else entirely different with its own characteristic behavior.

• Know that the electron configuration in atoms determines how a substance reacts and how much energy is involved in its reactions.

• Experiment and determine that the rates of reaction among atoms and molecules depend on the concentration, pressure and temperature of the reactants and the presence, or absence of catalysts.

• Know that the connections (bonds) form between substances when outer shell electrons are either transferred or shared between their atoms, changing the properties of substances.

• Know that the body processes involve specific biochemical reactions governed by biochemical principles.

• Know that the chemical elements that make up the molecules of living things are combined and recombined in different ways.

• Know that acceleration due to gravitational force is proportional to the mass and inversely proportional to the square of the distance between the objects.

• Know that electrical forces exist between any two charged objects.

• Describe how magnetic force and electrical force are two aspects of a single force.

• Know that the forces that hold the nucleus of an atom together are much stronger than electromagnetic force and that this is the reason for the great amount of energy released from the nuclear reactions in the Sun and other stars.

• Know that most observable forces can be traced to electric forces acting between atoms or molecules. Explain that all forces come in pairs commonly called action and reaction.

• Understand how knowledge and energy is fundamental to all the scientific disciplines (e.g. the energy required for biological processes in living organisms and the energy required for the building, erosion and rebuilding of Earth).

• Understand that there is conservation of mass and energy when matter is transformed.

• Know that nuclear energy is released when small, light atoms are fused into heavier ones.

• Know that temperature is a measure of the average translational kinetic energy of motion of the molecules in an object.

• Know that as electrical charges oscillate, they create time-varying electric and magnetic fields that propagate away from the source as an electromagnetic wave.

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• Know that the first law of thermodynamics relates the transfer of energy to the work done and the heat transferred.

• Know that the total amount of usable energy always decreases, even though the total amount of energy is conserved in any transfer.

• Know that the structure of the universe is the result of interactions involving fundamental particles (matter) and basic forces (energy) and that evidence suggests that the universe contains all of the matter and energy that ever existed.

• Know that technological problems often created a demand for new scientific knowledge and that new technologies make it possible for scientists to extend their research in a way that advances science.

• Know that scientists can bring information, insights and analytical skills to matters of public concern and help people understand the possible causes and effects of events.

• Know that funds for science research comes from federal government agencies, industry and private foundations, and that this funding often influences the areas of discovery.

• Know that the value of a technology may be different for different people at different times.

• Know that scientific knowledge is used by those who engage in design and technology to solvepractical problems, taking human values and limitations into account.

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TABLE OF CONTENTS-APPENDICES

Appendix 1: Glossary of Terms...................................................................................................

Appendix 2: Lab 1 Density of Water......................................................................................

Lab 2 Motion in one Direction...........................................................................

Lab 3 Motion in two Directions.........................................................................

Lab 4 Acceleration.............................................................................................

Lab 5 Speed of Sound ........................................................................................

Lab 6 Magnetism ...............................................................................................

Lab 7 Testing Chemical Changes ......................................................................

Lab 8 Visit a Planetarium ..................................................................................

Lab 9 Hunting for Rocks....................................................................................

Lab 10 Weather....................................................................................................

Appendix 3: Solutions to Problems .............................................................................................

Appendix 4: Great Scientists, Thinkers and Geniuses ................................................................

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APPENDIX 1 Glossary of Terms

• Acceleration – increase in velocity over time • Aggregate – a whole bunch of things • alternating current – electrical current that switches directions 60 times per second; usually 120 V

household current • amino acids – complex molecules that are the building blocks of life forms • AMU – atomic mass unit • Ångström – a very small unit of length named after a Swedish scientist • angular momentum – the energy of motion in a circle • antioxidants – organic molecules that neutralize free radicals • asteroid – minor planet orbiting sun • atomic fission – the splitting of an atomic nucleus into smaller nuclei • atomic fusion – the squeezing together of two or more atomic nuclei to make a heavier nucleus • atomic mass unit, or AMU – the mean weight of a mole of the average isotope of an element, in

grams • atoms – one of 100 or more individual elements, composed of one or more protons, and zero or

more neutrons in the nucleus, and electrons • balanced equation – a chemical equation that has an equal number of products as reactants • bases – solutions which have high pH; part of the DNA molecule • battery – a direct current source of potential • biochemistry – the chemistry of life • black hole – the destiny of a super massive star that collapses upon itself until it disappears in time

and space • breeder reactor – using multiple chain reaction processes to create atomic energy for generating

electricity • carbohydrate – a complex organic molecule that is made in a biochemical process and used for a

source of fuel (food) for plants and animals • carbon “family” – other elements in the same column in the Periodic table as carbon • carbon fusion – when 3 carbons come together to form an Iron atom • cartography – a branch of geography that deals with making and interpreting maps • celsius – the same as centigrade; a type of temperature scale. Named after a Scandinavian scientist • chemical burning – combining one or more atoms or molecules with oxygen to create an oxidized

product • chemical change – similar to burning, but does not have to combine with oxygen; the reactants and

products merely “switch partners” • climate – the average weather pattern in a certain region, taken over many years or centuries • climatic regions – five (based upon temperatures) or eight (based upon precipitation) regions as

observed from all over the world • clouds – puffy blobs of tiny water droplets, formed by cool air condensing the water vapor in the

atmosphere • cluster of stars – a group of a 100 to a million stars

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• coal and diamonds – two items made of carbon • colloidal suspension – when something is mixed with a solvent, the solute does not dissolve, nor

sink to the bottom, but stays suspended in the solvent • comet – dirty snowball orbiting Sun • complex carbohydrates – higher order carbohydrates, like potatoes • compound – two or more elements combined • conduction – transferring heat by touch; the characteristic of a substance that allows electrons to

flow in current • convection – the transfer of heat by movement • crest – the top of a wave • Crick & Watson – two scientists who discovered DNA • Crust – upper 50 km of Earth’s surface • Deuterium – heavy hydrogen – has one neutron • direct current – low voltage current that does not alternate • DNA – deoxyribonucleic acid – the double strand of proteins that dictates cell information • double helix – a twisted double strand like a spiral staircase • Earth’s magnetic field – the magnetic field of Earth that causes a magnetic compass to move;

caused by liquid outer core and Earth’s rotation • Earthquakes – movements of the crust and upper mantle of Earth • efficiency of burning – a number from 0% to 100%, to indicate how much of the reactants turned

directly into the products • electric current – how fast electric charge moves with time • electrolysis – separates water into hydrogen and oxygen by electricity. • electromagnet – an artificial magnet made by sending current through a wire that is coiled around

iron • electromagnetic radiation –the spectrum from Radio to Visible to Gamma • electrons – infinitesimally small particles that have a negative charge • element – one of 100 or more types of single atoms as listed in the Periodic Table • endothermic – a reaction which absorbs energy • energy – work; force multiplied by distance; power divided by time • enzymes – special proteins that help break down and rebuild cells • exosphere – the outer atmosphere of Earth • exothermic – a reaction that gives off energy • fact vs. fiction – fact is real; fiction is make-believe • Fahrenheit – a type of temperature scale named after a German scientist • Field Theory – a theory that assigns a value to each place in a space or volume • Force – a type of energy that is need to accelerate a mass • free radicals – dangerous molecules that are electron-deficient and that roam cells stealing

electrons, thus damaging the cells, and increasing the chances of disease and aging • frequency – how many times something occurs each second • galaxy – a large group of stars, numbering at least 1 billion • gamma rays – most energetic of all light • gasoline – a hydrocarbon fuel with 8 carbons • GeoChemical Rock Cycle – the cycle of Earth’s crust, from magma to rocks, and back to magma

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• Geography – a branch of geology that studies the surface of Earth and its features • Geology – the study of Earth, including its rocks, soils, minerals, core, etc. • Glucose – the simplest of sugars with 6 carbons • Glycogen – another sugar • Half-life – the time it takes for a radioactive isotope to decay to half its original amount • heat capacity – the ability of a compound to transfer heat • heat transfer – a way to have heat energy reach equilibrium • helium fusion – turning helium into Iron • hertz – the unit of frequency, named after a German scientist • heterogeneous – all mixed up • homogeneous – all blended together • hydrates – crystals with water molecules • hydrocarbon – a molecule with one or more carbons attached to one or more hydrogen atoms • hydrogen fusion – the creation of helium by bringing 4 hydrogens together • igneous – the most basic rock • Inner and Outer Core – the inside of a planet • ion – a charged particle of any kind • ionosphere – an upper level of the atmosphere where most atoms are ions • isotope – one of several “versions” of an element, depending on the number of neutrons in the

nucleus • Kelvin – a type of temperature scale named after a British scientist • Lactose – a type of sucrose (sugar) in milk • Law – something that must be true • Law of Gravity – the rules of how gravity works; mass attracts mass • Length – how long something is • magnetism – the polar alignment of iron atoms in a rock or mineral • magnetite – a rock that is naturally magnetic; has much iron inside • man-made magnet – electromagnet • mantle – part of Earth’s interior that is below the crust, but above the core • mass – the amount of something • Maxwell’s 4 Equations – the fundamental simple formulae for “everything” • Mesosphere – the middle atmosphere, above the troposphere, but below the ionosphere • Metamorphic – a very dense rock in the GeoChemical Rock Cycle • Meteor – a flash of light made by a falling meteorite while rushing through the air in flight, and is

usually seen at night • Meteoritics – the science of studying meteorites • Meteorology – the science of studying weather and climate • Meters – the unit of length in the metric system • meters per second – the unit of speed or velocity in the metric system • meters per square second – the unit of acceleration in the metric system • metric system – a uniform system that uses powers of ten • microwaves – one of the “colors” of light, shorter than Radio, but longer than infrared • Mixture – two or more substances together • Mole – a very large number, equal to 6.02 x 1023

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• Molecules – a combination of two or more atoms • Momentum – the energy of motion, mass times velocity • mono-saccharides – single sugars • Moon – the name of Earth’s larger natural satellite • Motion - moving • natural magnet – one created in nature • neutrons – neutral small particles about the size of a proton • Newton’s Three Laws of Motion – describes how particles should act under forces • nuclear change – when the number of protons in the nucleus changes • nucleic acids – acids that build DNA • nucleus – the “brain” of a cell; also, the center of an atom • Other sciences – Astronomy, Geology, Meteorology, Anthropology, Biology, etc. • permanent magnet – one that is naturally made or man-made, as in a rock • photosynthesis – the natural plant process of taking carbon dioxide, water, and solar energy, and

creating food, glucose, for the plant • physical change – different shape • planet – an object that orbits a star, except for comets • poly-saccharides – complex sugars • potential – stored energy (in mechanics or electricity) • power – energy used per unit time • power generator – one of many devices used to create electricity • powers of ten – using 10’s and decimals • precipitation – rain, snow, etc. • product – the end of a reaction • propane – a hydrocarbon gas fuel • proteins – combinations of amino acids • protons – tiny, charged particles at the center of an atom • quarks – one of six types of sub-atomic, and sub-proton particles • quasar – nucleus of newly forming galaxy at the edge of the Universe;short for quasi-stellar radio

source • radiation – either emitted energy waves, or decayed particles from radioactivity • radio waves – energy waves that are very long and have low energy • radioactivity – the natural decay of isotopes • reactant – the left side of the chemical formula; the stuff that is changed • Red Giant – a phase of star’s life near its end; very large, cool star • Resistance – the ability to resist electrical current in a conductor • Revolution – one cycle around an object, such as the Moon orbiting Earth • RNA – a single strand of genetic material, “half” of a DNA. Stands for Ribonucleic Acid • Rotation – spinning on an axis, such as Earth turning once every day • Sedimentary – the middle phase of a rock’s life in the GeoChemical Rock Cycle • Seismology – the study of “seisms” or quakes (earthquakes) • simple carbohydrates - sugars • Solar System – the Sun’s “family” of moons, planets, comets, meteors, asteroids, and the Sun itsel • Solute – the material dropped into a liquid to be dissolved

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• Solution – the final product of a solvent and solute • Solvent – something that dissolves other stuff; water is a solvent for salt; turpentine is for paint;

etc. • Space – an entity that separates events in time; 3-D or more • space-time – a fabric that interweaves space and time • speed – movement over time • speed of light – the speed light can travel in one second; 300,000 km/s • speed of sound – the speed sound can travel in a medium; in air, at STP, it’s 343 m/s • star – self-sustaining nuclear-burning, huge ball of hydrogen • starch – complex carbohydrate • static electricity – built up electrons that are not moving • stellar reactions – the nuclear processes that occur inside stars • substation – a mini “way-station” for the transmission of electrical power • sucrose – the simplest sugar • Sun – our self-sustaining nuclear-burning, huge ball of hydrogen that is about 150 million

kilometers from Earth • temperature field – a region of volume where the temperatures vary from spot to spot • temperature scales – different designs of measuring temperature • thermometers – device that measures heat (temperatures) • theory – any idea • time – the entity that separates events in space; unit is the second • transformer – a “box” that accepts electrical power from a substation and sends it into a house or

building • tritium – very heavy hydrogen; has two neutrons in the nucleus • troposphere – lowest level of the atmosphere; we live there • trough – the bottom, or lowest, part of a wave • Tsunami – same as “tidal wave,” a huge wave (or wall) of ocean water created by an undersea

earthquake • Unified – all together • units in the metric system – meter, kilogram, etc. • units in the old system – foot, pound, etc. • units of momentum – kg-m/sec • units of space - meter • units of time - second • universe – everything that there is in our time and space • velocity – how fast something is moving and in what direction; meters/second • visible spectrum of light – the colors of ROYGBIV • voltage – the potential electrical energy • wave packet – a series of waves all grouped together • wavelength – the distance from one crest to the next crest • weight – this is a force; Newtons in metric; pounds in old system • White Dwarf – in the life span of a star, this is near the end, after a Red Giant, and it’s very small,

and very hot • Work – same as energy; the product of force and distance

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C. Personal Errors - caused by the experimenter him/herself

D. Quantitative Error

The true answer is one gram per cubic centimeter = 1.0 gram/cc = 1.0 g/mL. To find out your percent error (%), here is what you do: 1. Subtract your answer from the true answer, then take the absolute value of that:

| (True Answer - Your Answer) | = | T - Y | = _________ 2. Divide this number by the True answer: | T - Y | / T = __________ 3. Multiply this number by 100, and attached the percent sign, %, after it; in other words, multiply your answer in #2 by 100% = ____________

E. Qualitative Error

1. Is your answer correct to within 10%? If so, good job, and congratulations! 2. However, if your answer is more than 10% off, please list some things that you would tell another experimenter to do (or not do) to make the answer have a smaller error. In other words, what do you think contributed to the error? 3. Is your answer more than 100% off? Please do the experiment again, or spend a lot of time trying to explain how you possibly could have been so wrong.

VIII Questions (answer from your experiment, or from books, InterNet, or other sources. Don’t ask other people. 1. What is the density of ocean water (salt water)? Is that more, or less, than the density of tap water?

2. Is it easier for a human to float in the ocean, or in a fresh water lake? Explain why or why not. 3. Is solid water (ice) denser, or less dense, than liquid water? Explain.

4. How many gallons of water on on planet Earth? Physical Science Lab 2 I Title: Motion in One Direction

II Purpose: To study linear motion III Equipment • Calculator

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• x-rays – a very high energy light ray

APPENDIX 2 Physical Science Lab #1 I Title: Density of Water II Purpose: To determine the density of tap water; to learn the proper scientific method for lab reports; to get used to measuring. III Equipment Needed 1 - Small glass tumbler 1 – Measuring cup Scale that weighs ounces of solid food Tap water Pen, calculator, lab book, etc. IV Procedure 1. "Weigh" the empty, dry measuring cup on the scale -- record answer in fractions of an ounce. (e.g. 3.5 oz.) [Record all data in Section V (Data & Calculations) below.] 2. Pour exactly ¼ cup water in measuring cup. 3. "Weigh" the measuring cup with the water in it -- record answer in fractions of an ounce 5. Find the "weight" (i.e., mass) of the water in ounces, and record this. Do this by subtracting the weight of the dry cup from the one filled with water. Convert oz. to grams. 6. Find the density of tap water, by dividing the mass of the water by the volume of the water 59.15 mL (see below) or (. Give the answer in grams per milli-liter (mL), which is the same as grams per cubic centimeter (cc). Record this answer. (Do all calculations in Section V below). Conversion: ¼ cup water = 2 fluid ounces = 59.15 mL = 59.15 cc. Conversion: 1.0 pound = 453.6 grams V Data & Calculations 1. Mass of dry measuring cup (in fractions of an ounce) __________________ oz. ___________ grams 2. Mass of cup plus ¼ cup (59.15 mL) of water _____________ oz. ___________ grams 3. Mass of the water (subtract #1 from #2) _____________ oz. ___________ grams 4. Density of the water (Divide #3 by 59.15 mL) ____________ grams/mL VII Error Analysis

A. Random Errors – ones that you can’t control. However, if you repeat the experiment several times, all random errors will cancel out

B. Systematic Errors – caused by faulty equipment or from faulty logic when performing the

experiment

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• Marble or ball bearing IV Procedure • Measure a distance of 1.0 meter from the edge of a table, from A (on the table) to B (the edge of

the table). • Roll a marble from A to B several times to determine its average speed. Write that down in

meters/second (Divide 1.0 meters by the number of seconds.) • Measure how far the top of the table is from the floor. • Place the meter stick on the floor from the edge away from the table. • Roll the marble and start your stopwatch as it reaches the edge, B. Use the meter stick to measure

where the marble hits the floor – that will be point C – and stop the watch. • Find out how fast the marble was going in the x-direction (the forward direction) between B and C

(the distance to point C measured by the meter stick on the floor divided by the number of seconds that the marble took to fall.)

• Find out how fast the marble was going in the y-direction (downward) from B to C (the distance from the table top to the floor divided by the time the marble took to fall).

• Repeat the experiment without any forward motion; just put the marble at B, and gently roll it off the table on to the floor, while timing how long it takes to fall. Find out the speed of the marble in the y-direction (downward) from B to a point directly below, on the floor. Call this point D.

V Data, Observations, Calculations Remember to convert inches to meters by dividing by 39.37. • What is the average speed of the marble while rolling along the table top? _________ • What is the distance from the table top to the floor? ___________m • What was the distance from the edge of the table to point C, where the marble hits the floor?

___________m • What was the forward speed of the marble from B to C? (Divide the distance by the time on the

stopwatch). • What was the downward speed of the marble as it fell from B to C? • What was the downward speed of the marble as it fell from B to D? • Compare, Contrast, and Explain the two downward speeds. VI Results

Explain or magnify the level of success or failure VII Error

A. Random B. Systematic C. Personal

VIII Problems 1. A rolling marble, at 0.20 m/s, falls off the edge of an 80.0-meter high table. How long does it take to reach the floor? How far from the table’s edge, horizontally, will it land? Assume no air resistance.

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2. Jumping Jack Flash consumes a pint of high quality barley soda, while floating across the sky in a hot air balloon. Not wishing to retain the empty container, he drops it over the edge while no one is looking. A hapless native on the ground is struck by the empty bottle 20.0 seconds later. What was the height of the balloon if it were motionless at the time of the bottle drop? What is the name of the now-deceased native? Does this sound like a plot for a movie? Which one? Use the relationship that h = ½ g t2, where “h” is the height in meters; “g” = 9.8 m/sec2 and is the acceleration of gravity; and “t” is the time in seconds. Physical Science Lab 4 I. Title: Acceleration II. Purpose: To observe objects moving at a constant acceleration. Graph the relationships; interpret the graphs III. Equipment A toy car of 4 wheels A ramp (can be made with a board and a brick, books, anything) Brick Graph paper, pencil, ruler Masking Tape Meter or Yard Stick Protractor (you’ll also need one for your Pre-Algebra and Algebra courses) Calculator Stopwatch IV. Procedure

1. Find a clear, flat surface a few meters long 2. Set up a ramp system to form a skinny right triangle, with angles approximately 90-80-10 or 90-70-

20. Once set up, measure the angle precisely with a protractor, or measure the 3 sides of the right triangle precisely with a ruler or yard stick

3. Use the back of the ramp as a starting point. Place car on starting point, with its back wheels behind the ramp (so it doesn’t start moving yet)

4. Lift the rear wheels of the car, carefully, and start the stopwatch simultaneously. At the instant that the back wheels clear the bottom of the ramp, stop the watch. Record the time.

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5. Repeat step 4 four more times. Record. Average the 5 time trials. 6. Place the car at the starting point, and let it go, as before. However, DO NOT start the watch until it

crosses the bottom of the ramp. Allow the cart to come to rest, and then stop the watch. Measure the distance traveled. Record. Repeat 4 more times, then take the average. Record.

V. Data & Calculations Remember to express inches as a decimal. E.g 27.75 in. Remember to convert inches to meters by dividing by 39.37 1. Length of ramp ______________m 2. Height of ramp ______________m 3. The value of the “skinny” angle in the right triangle ____________ degrees. 4. Average velocity of the car while on the ramp ______________m/s 5. Average acceleration of the car while on the ramp ____________m/s ² 6. Distance that the car traveled after clearing the ramp: ______________m 7. Average velocity during travel (after leaving ramp) ______________m/s 8. Average acceleration during travel (after leaving the ramp) _____________ m/s ² 9. Make graph of distance vs. time while on the ramp. (Time along horizontal axis.) 10. Make a graph of velocity vs. time while on the ramp. (Time along horizontal axis) 11. Repeat 9 and 10 for the periods on the flat surface (after leaving the ramp). VI. Results The purpose of this lab was to observe objects moving at constant speeds and changing speeds. Explain how well this was achieved. VII. Error Analysis A. Quantitative The acceleration on the ramp should be a = g x sin �. Remember that “a” stands for the acceleration of the car; “g” = acceleration of Earth’s gravity = 9.8 m/s2, and � is the skinny angle that you made in your ramp design. The sin � is the trigonometric function. [To find out what it is, you can go to http://www.math2.org/math/trig/tables.htm, 01/18/2006, or if you have a math & science calculator, merely punch in that angle and the button that says “sin” which stands for sine of the angle.] Use the acceleration, “a” that you find as the truth, and compare it with YOUR ramp acceleration. Find percent error. B. Qualitative

1. Personal 2. Systematic 3. Random

VIII. Questions

1. Did the car speed up, slow down, or stay the same speed as it traveled down the ramp? Explain or support.

2. Did the car speed up, slow down, or stay the same speed as it traveled past the end of the ramp? Explain or support.

3. What are the shapes of the graphs you made? 4. How far did the cart travel during each 1.0-second interval on the ramp? Beyond the ramp?

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Physical Science Lab 5 I Title: Speed of Sound II Purpose and Theory To study the concept, and speed, of sound. Theory: in mechanics, the length of the wave (aka wavelength) multiplied by the frequency of the wave is equal to the speed of the wave. In this case, the wave we are talking about is a sound wave in air. In the form of an equation, it is: � x � = v where the wavelength is represented by the Greek letter, � (pronounced "lambda"), and the frequency is represented by the Greek letter � (pronounced "new"). The speed is represented by the Roman letter v (aka velocity). The letter "x" in the formula stands for "multiplied by." Sound travels the fastest in a solid, then next fastest in a liquid, and finally, the slowest in a gas (air). In the depths of space where it is a vacuum (no air or gas at all) sound does not travel. Sound waves need a medium to travel through. In this experiment, you will hear sounds that will grow louder or softer as you move towards or away from them. You will also notice the farther you get, the more apparent it is that sound travels slower than light. III Equipment • 2 participants • a noisemaking device (could be a voice, but it must be the same noise and loudness each time) • stopwatch • meter or yard stick IV Procedure

1. Find a relatively quiet street or park 2. Mark off 100 meters in 10 meter increments or 100 yards in 10 yard increments 3. Designate a “zero” point, and have your assistant stand there with the noisemaker device 4. Walk 10 meters or yards away and, at your signal, have your assistant make a noise 5. Listen carefully how loud the noise is. 6. Walk to 20 meters or yards and repeat the scenario. 7. Continue every 10 meters or yards until you reach 100 meters or yards 8. Return to the zero point and have your assistant walk out to 10 meters or yards. 9. Make the noise at the same time that you make a visible gesture towards your assistant, so

he or she will know that the sound went off. If you had a starter pistol (gun) the assistant may see a plume of smoke the instant the gun is fired, but you can be creative.

10. Start the stopwatch the instant you make the noise 11. Instruct your assistant to raise his hand immediately upon hearing the noise. 12. As soon as you notice his hand go up, stop the watch. 13. Do this for each 10 meter or yards increment until 100 meters or yards has been covered.

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V Data, Observations, Calculations A. Make table of data for when you walked further away from the noise. The first column

would be “position,” from 1 to 10. The second column would be distance, from 10 up to 100. The third column would be sound level. Use the loudness of the sound to be equal to 1.0 at the distance of 10. If the sound is only about half as strong at 20 than it was at 10, put 0.5 for 20. If, however, the sound at 20 were only 1/4th as loud, put 0.25. Continue this all the way to the 100. If you cannot hear any sound at any of the positions, then put zero (0.0).

B. Note if the wind is blowing and in which direction. The ideal situation would be calm (no wind). If the wind is blowing in your direction as you are walking away, the sound will travel farther. If the wind is blowing towards your assistant as you walk away, the sound will not travel very far.

C. Make a second table of data for when you assistant walks away, stops, waits to listen to the noise, and puts up his/her hand. The three columns will be position, distance, and time (from the stopwatch)

VI Results

Explain the level of success of the lab. Don’t just say “Well, it was successful because …” and that kind of thing. The speed of sound in normal air is about 343 meters per second, or about 1100 feet per second. If you were to see lightning in the distance during a storm, and then counted the number of seconds until the thunder reached your ears, then you could tell how far the lightning bolt struck. If you wait for 5 seconds, that is about 5500 feet, or just about one mile. If you can do this experiment safely during a lightning and thunderstorm, that would be ideal. However, it’s not always safe!

If you have the chance, try repeat the lab in a liquid, i.e., in a swimming pool. You will notice the sound travels much faster. VII Error Analysis

1. Personal 2. Random 3. Systematic

VIII Questions 1. What is the value for wavelength of a sound that has a frequency of 1,000 Hz? (� = 1000 / sec). Use the value for speed of sound in VI Results. Use metric units only. 2. Does the speed of sound depend on loudness? Why, or why not? 3. Does the speed of sound depend on AIR temperature? Why or why not? 4. What would an orchestra sound like, if the higher frequencies traveled faster (and thus got to the audience earlier) than the lower frequencies?

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Physical Science Lab 6 I Title: Magnetism II Purpose: To study magnetism. III Equipment • Magnetic Compass • Steel furniture (such as a Filing Cabinet) Not aluminum or PVC • D-Cell Battery (1.5 volts) • Insulated copper wire, about 1.0 meter from a hardware store • Large, iron nail (Not steel) from a hardware store • Box-shaped battery, 9.0 volts IV Procedure- Part I 1. Procure a functioning magnetic compass. Test it in Earth’s magnetic field. 2. Locate a metal filing cabinet, or similar. 3. Walk in the direction of the filing cabinet. 4. Stop in front of the filing cabinet. 5. While steadily holding the magnetic compass in your hand, with the compass parallel to the floor,

slowly move the compass to the top of the filing cabinet, as close to the filing cabinet as possible, without touching it.

6. Now, slowly move the compass earthward, while continuously observing any changes in the direction of the compass needle. Record your observations.

Part 2 1. Take your iron nail, and test it for a magnetic field, similar to what you did for the Filing Cabinet.

Record. 2. Remove about 1.0 cm of insulation from both ends of the insulated wire. 3. Wind your ~ 1.0 meter of insulated wire tightly from just below the nail’s flat head, to just above

its sharp point. 4. Connect one end (a “lead”) of the wire to the (+) positive terminal on the battery (top), and the

other end to the (-) negative terminal of the battery (bottom). 5. Test your electrical, magnetically-induced nail for a magnetic field, as you did in Part 2. Step 1.

Record. 6. Switch the leads on the terminals, and repeat Step #5. Record your observations. 7. Repeat with a 9.0 V battery (shaped like a box). V Data, Observations, Calculations

This is where you write your observations and stuff. NOT in section on IV Procedure. VI Results

You were supposed to have learned about natural and induced magnetism. Describe how successful you were. Compare/contrast the effect on the compass when you used the 9.0 V battery.

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VII Error 1. Random 2. Personal 3. Systematic

VIII Questions 1. Did the compass needle change direction, at all, during your pass over the Filing Cabinet? Explain. 2. Did the compass needle change direction, at all, during your pass over the naked iron nail? Explain. 3. Did the compass needle change direction, at all, during your pass over the electrical magnetically

induced iron nail? Explain. 4. Research to find out the strength of Earth’s magnetic field, on average, and give the magnetic field

strength here in South Florida, and at 4 other locations (of your choosing) on planet Earth, but no where near South Florida.

Physical Science Lab 7 I Title: Testing Chemical Change II Purpose To see the way a test kit changes with acids, bases, and neutral fluids III Equipment • A swimming pool test kit • Acid (vinegar, or lemon juice) • Base (colorless ammonia) • Water IV Procedure 1. Test each of the fluids above and observe, record each color V Data and Calculations VI Results VII Error VIII Questions

1. Why do Swimming Pool service persons use test kits? 2. What would happen if your swimming pool had too much acid? Too much base?

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Physical Science Lab 8 I Title: Visit A Planetarium (optional) II Purpose To learn about stars and planets from a planetarium III Equipment • A local planetarium • Pad of paper, clip board, pen or pencil • RED – lighted flashlight (not a red colored flashlight) IV Procedure

1. Locate a local planetarium. If you are having trouble, contact the Miami Space Transit Planetarium, Buehler Planetarium (in Davie, Florida), or the Aldrin Planetarium in West Palm Beach, and ask them.

2. Determine the schedule of show times and dates 3. Attend one of the planetarium shows, and take notes 4. Write up the notes on what you learned about the stars and planets

V Data and Calculations VI Results VII Error VIII Questions

1. Why is this theatre called a planetarium if you also see stars? 2. How many planetaria are in the United States?

Physical Science Lab 9 I Title: Hunting for Rocks II Purpose and Theory. To find as many types of rocks as possible. There are three main types of rocks: Igneous, Sedimentary, and Metamorphic. The object is to find at least one of each type of rock on your expedition outdoors. You may search your yard, or a park, or the beach, or wherever you may find rocks. However, all three types may not necessarily be in the same location. III Equipment • Comfortable Shoes • Magnifying glass • Small hammer • Sack to put rocks in

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IV Procedure 1. Select the place(s) you choose to look 2. Search the area(s) that you have selected 3. Find one of each type of rock, and collect the sample

V Data and Calculations (The data will be your rocks) VI Results VII Error VIII Questions

1. What is the difference between these three types of rocks? 2. How old are the different types of rocks? 3. Explain the GeoChemical Rock Cycle

Physical Science Lab 10 I Title: Weather II Purpose To study wind, sky, rain, clouds, and other weather-related items. III Equipment • Access to a weather reporting source (newspaper, TV, radio, Internet) • Calendar • Thermometer • Barometer (optional) measures atmospheric pressure • Anemometer (optional) measures wind speed IV Procedure

1. Check local listings of the highs and lows for the past 5 days. Record 2. Check local listings of the weather conditions for the past 5 days (cloudy, windy,

rainy, sunny, etc.) 3. Observe the weather over the next 5 days (highs, lows, conditions) and record. 4. Make a prediction of the weather over the next 5 days (without cheating and looking

in the paper). Record. 5. After that 5 days, check the local listings of what the weather really was, and

compare what really happened with what you had predicted. V Data and Calculations (The data will be your table of temperatures, etc., vs. dates)

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VI Results Well? VII Error If you were not exactly correct, why not? VIII Questions

1. Why do they call meteorology an inexact science? Isn’t science exact? 2. How many climate zones are in the United States? 3. Which city has the most moderate, or, even temperature, in the U.S.?

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APPENDIX 3

Solutions to Problems Unit 1: Scope of the Physical Sciences Lesson 1: One’s place in the Cosmos

Problems 1. An infinite number of numbers. 2. An infinite number of galaxies. 3. Humans are the most intelligent life form on Earth. 4. Humans have vast reasoning and can build complex machines and travel to the Moon. Lesson 2: Direction of Time and Space Problems: 1. It is time to learn. My chronometer tells me. 2. There are 24 times zones around the globe, each approximately 15 degrees wide – in longitude.

The zones start with Greenwich, England (at 0 degrees) and increases one hour per time zone as one moves eastward, and decreases one hour per time zone as one moves westward. The International Dateline, which is on the opposite side of the world from Greenwich at 180 degrees, marks the separation of one day from another. For example, just west of that line it may be Wednesday, while just east of that line would still be Tuesday.

3. The history of Daylight Savings Time started with Ben Franklin, then was brought up by a British scientist, then later used in World Wars I and II. Eventually our current system was enacted in 2007.

4. On Earth the place that is exactly 12 hours ahead of the Eastern Time Zone is in Southeast Asia (Thailand, Indonesia, etc.)

Unit 2: Mechanics Lesson 1: Weights and Measures Problems 5. 5 feet is 60 inches. Adding 10 inches makes it 70 inches. Each inch is the same as 2.54 centimeters,

so, 5’ 10” = 177.8 cm, or 1.778 meters 6. 200 pounds on Earth is 200 / 2.2 = 90.9 kilograms 7. There are 1,000 grams are in a kilogram. 8. The “yard” was defined as the length of the arm of some British King.

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Lesson 2: Motion Problems 5. 1,000 miles per hour 6. If your Aunt Mary lived 100 miles from you (by car), how fast should you drive your car (on

average) to get to her house in • 2 hours? 50 miles per hour • 90 minutes? 75 miles per hour (that’s fast!) • 1 hour? 100 miles per hour (don’t get a speeding ticket!)

7. Now, imagine that you take a road trip of 80 miles, from A to D, but you have to do it in segments. Let’s say you drive from A to B in 30 minutes, B to C in 45 minutes, and C to D in 15 minutes. The distance from A to B is 15 miles; from B to C is 45 miles, and C to D is 20 miles. • How many miles did you drive from A to D? 80 miles • How many minutes did it take you to drive from A to D? 90 • How many hours did it take you to drive from A to D? 1.5 • What was your average speed during your trip from A to D? 80/1.5 = 60 mph

8. 10 mph/sec = about 16 km per hour / sec = 16,000 meters per hour per second = 4.44 m/s² Lesson 3: Energy, Force, Momentum, Power Problems 7. Divide 2000 pounds by 2.2 pounds per kilogram = 909.1 kilograms. Multiply 30 miles by 1.6

kilometers per mile = 48 kilometers. Now we have a 909-kg car traveling at 48 km/hour. But we must change it to meters per second. 48 km = 48,000 meters and 1 hour = 3600 seconds, so divide 48,000 by 3,600 = 13.3 m/sec. So the momentum, p = m x v = 909 x 13.3 kg-m/sec = 12,120 kg-m/sec (approx).

8. The washer travels the length of the circumference which is c = 2 � r = 2 � (1 meter) = 6.28 meters every half second, or twice that distance every second, so v = 12.56 m/s. The angular momentum is p = m x v x r = (0.01 kg) x (12.56 m/s) x (1 meter) = 0.1256 kg-m/sec. Remember that 10 grams = 0.01 kg.

9. Since F = m x a, then F = (0.250 kg) x (50 m/s2) = 12.5 kg-m/s2 = 12.5 Newtons. 10. Since Energy = Work = F x distance = (12.5) x (30) = 375 Newton-Meters = 375 Joules 11. Since P = E/t, and P =100 Watts = 100 joules per second, then the energy used, per second, is 100

joules. 12. James Cavendish was the man who discovered the Universal Gravitational Constant, G. Lesson 4: Heat and Temperature

Problems

7. To convert 80 degrees F into Celsius, first you must subtract 32 degrees, then multiply that by 5/9. Or, C = 5/9 (F - 32), where 5/9 = 0.555556. Therefore, C = 5/9 x (80 – 32) = 0.55556 x 48 = 26.7, or approximately 27 C.

8. All hydrocarbons burnt efficiently will give only water and carbon dioxide.

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9. If you are cold, the fastest method to get warm is conduction, as the heat will transfer immediately to you through your skin (like in a hot bath).

10. The Sun gives heat to the Earth by Radiation. 11. Styrofoam has a higher heat capacity than copper since it takes a long time to warm up and doesn’t

accept heat well. Copper heats up and cools off quickly. 12. Hydrocarbons are made only of carbon and hydrogen, and are immediately combustible.

Carbohydrates are a starchy food created by plants, and include the atom oxygen. Lesson 5: Waves – Light and Sound Problems 7. Heinrich Rudolf Hertz was a German scientist who studied light waves. 8. Anders Ångström was a Swedish astronomer who studied light waves. 9. The frequency of a beam of red light whose wavelength, � = 6000 Ångströms, and the speed of

light is a constant, c = 300,000 km/sec, then the frequency, � = c/ �= 300,000 km/sec divided by 6000 Ångströms = 50 (km/ Ångströms) per second. This is not really an understandable answer, so we need to convert everything to meters first. So, wavelength, � = 6000 Angstroms = 600 nm = 6 x 10–7 meter. The speed of light, c = 300,000 km/sec = 3 x 108 meters/sec. Thus, if � = c/� = 3 x 108 meters/sec divided by 6 x 10–7 meter = 0.5 x 1015 which equals 5 x 1014 Hz. = 5 x 108 MHz

10. The speed of sound at STP (standard temperature and pressure) is about 342 m/sec. 11. If you see an ocean wave hit the beach every 8 seconds, its frequency is 1/8 per second, or 0.125

Hz. 12. A typical radio wave which has a frequency of 560 kilohertz has a wavelength of �= c/� = (3 x

108 meters/sec) / (5.6 x 105 Hz) = 536 meters. Unit 3: Electricity and Magnetism Lesson 1: Electricity: Current, potential, and power Problems 6. There are 6.24 x 1018 electrons in 1.0 Coulomb of charge. 7. The proton is 1800 times heavier than the electron. 8. Ben Franklin studied static electricity. 9. The electric force of attraction between a proton and an electron is 9.2 x 10-8 N. 10. If Mp = 1800 Me, the gravitational force of attraction between a proton and an electron is 4 x 10-47

N. Lesson 2: Types of Current – D.C. and A.C. Problems 4. A typical Tesla coil may have a potential of 10,000 volts, but its current is very low, and its

frequency is very high. On the other hand, a shock from household plug could be fatal, since the current is high and the frequency is low. It’s the current that kills, not the potential.

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5. There are two cylinder transformers on my property lines – one between my yard and one neighbor’s yard, and another between my yard and yet another neighbor’s yard. It is on a telephone pole, about 20 feet up. as you can. In most places, they are large, gray cylinders that are placed high on telephone poles.

6. The nearest substation is about 1 mile north and 1 mile west. It is a large area, with many metal poles, transformers, and other “tech-looking” things. Large, heavy power lines come from it and leave from it.

Lesson 3: Magnetism Problems 5. If you take a magnet and place it near a pile of sawdust, nothing happens, as sawdust, which is

made of wood, is an insulator, and not made of iron. It is not attracted to a magnet. 6. If you put a magnet near a number of paper clips, they will be attracted to the magnet, as they are

made of iron (except plastic paper clips). 7. When you put a magnetic compass near an electrical wire, when the object is turned “on,” the

needle moves, as the wire acts like an electromagnet. 8. An electromagnet is made of moving electrons, which create a negative magnetic pole, and create a

magnetic field. Lesson 4: Electromagnetic Radiation Problems 5. There are 7 colors in the rainbow: ROYGBIV 6. There are 6 “colors” outside the rainbow: Radio, Microwave, Infrared, Ultraviolet, X-Ray, Gamma

Ray 7. The Plant is the life form that uses light to make food. 8. The most energetic electromagnetic radiation is gamma ray. Unit 4: Nuclear and Atomic Reactions Lesson 1: Small Particles Problems 5. There is only one electron in a neutral hydrogen atom. The lead atom has 82. 6. There are NO neutrons in a neutral hydrogen atom. The neutral lead atom has 125 neutrons. 7. There are 6 types of quarks. Their “names” are “up, down, charm, strange, top, and bottom.” 8. Murray Gellman of CalTech was the scientist who suggested the existence of quarks

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Lesson 2: Building Blocks of Elements Problems 5. The proton-proton reaction to create helium from hydrogen is:

41H1 = 2 He4+ 2β+ + Energy 6. The heavier and more complex elements are made one at a time from the fusion of hydrogen,

helium, atoms, etc. 7. Positrons are positive electrons. 8. Matter turns into energy via E = mc2, where “E” is the energy, “m” is the mass, and “c” is the

speed of light.

Lesson 3: Nuclear Energy

Problems 1. The “equation” for fusion to change hydrogen into helium is

41H1 = 2 He4+ 2β+ + Energy

2. The reaction for nuclear fission using Uranium to give energy - in the fission reaction with U-235, the nucleus is bombarded with a neutron, and the nucleus splits into two smaller elements, Barium and Krypton. It also gives off about 200 Million Electron Volts (200 MeV) that can be used peacefully to power homes and businesses.

3. Four atoms of hydrogen are needed to create 1 atom of helium. 4. Uranium-238 is used to create the breeder reactor. Unit 5: The Elements – Periodic Table Lesson 1: The Elements – Periodic Table Problems 6. A mole of Helium gas has 6.02 x 1023 atoms. 7. The AMU of Carbon is 12.0 grams 8. An isotope is one of several “versions” of a particular atom or element. 9. After 3 half lives, there would be 125 grams left of original Radium. (after 1 half life, 500; after 2

half lives, 250; after 3, 125). 10. Dmitri Mendeleyev created the Periodic Table. Lesson 2: Mix n’ Match – Compounds, Mixtures and Aggregates Problems 5. The desalination of sea water takes place when the sea water is separated into water and salt. This

can be done by evaporating the water away, and then cooling it to become a clear liquid. The dry salt is left behind.

6. You have to “shake before using” salad dressing because it is a mixture.

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7. Concrete is heterogeneous. 8. The most efficient way to ingest minerals is by colloidal suspension. Lesson 3: Chemical Change Problems 5. The chemical equation for electrolysis is = 2H2O + Energy = 2H2 + O2 6. The chemical equation for burning gasoline is

2 C8H18 + 25 O2 = 16 CO2 + 18 H2O + Energy 7. The chemical equation for fusing hydrogen into helium

4 1H1 = 2He4 + 2�+ + Energy 8. The three states of water are solid (ice), liquid (water), gas (vapor). Lesson 4: Chemical Formulae and Balancing Equations

Problems 5. To balance the equation CH4+ O2 = CO2 + H2O, we need the same number of atoms of each

element on each side. So, CH4+ 2O2 + 2H2O + Energy 6. Completing, and balancing, the equation is C3H8 + 5O2 = 3CO2 + 4H2O + Energy 7. The products in the burning of gasoline are CO2, H2O, and energy 8. No atoms are changed into other atoms. Unit 6: Organic Chemistry Lesson 1: The Element Carbon Problems 6. Why, or why not, would it be a good idea to get a ring with coal on it? Well, it’s very cheap, but

you’d have to put it under pressure for millions of years, or get superman to crush it for you. 7. Before it becomes a diamond, other phases must it go through includes rotting plants, peat, coal,

and then diamond. 8. In 1866, a boy discovered a shiny rock in South Africa, along a river bank, that turned out to be a

21-carat diamond. 9. The name of the fictional stone creature in Star Trek is the Horta. 10. Mining for diamonds in South Africa is one way to get diamonds. Another, “other world” way to

do it is to pick up meteorites.

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Lesson 2: Hydrocarbons Problems 4. The chemical combustion formula for burning of gasoline is 2C8H18 + 25O2 = 16CO2 + 18H2O +

ENERGY (heat) 5. Hydrocarbons are from dead dinosaurs. 6. Candles are heavy hydrocarbons, and do not explode. Lesson 3 Problems: Carbohydrates 7. The similarities between carbohydrates and hydrocarbons include large numbers of hydrogen

atoms and carbon atoms. Plus, both are sources of fuel; one for machines, one for animals. The differences between carbohydrates and hydrocarbons include having hydrates (water molecules) as part of the carbohydrate, and while hydrocarbons are combustible and can burn in air, carbohydrates are broken down and “burned” within cells.

8. Hydrates are compounds that have water molecules as part of their crystal structure. 9. The simplest sugar is Glucose. 10. Plants make food through a process of photosynthesis: they take in carbon dioxide, water, and solar

energy, and create glucose and oxygen. 11. Humans can’t make food as plants do since we don’t have chlorophyll, or the chemical processes

for turning the sun’s energy into nourishment. 12. Sucrose is better for a short term “boost in energy,” and starches (bread, potatoes, corn) are better

for long-term endurance. Lesson 4: Biochemistry Problems 9. “Biochemistry” is the chemistry of life. 10. The difference between RNA and DNA include the single vs. double chain, and the different bases. 11. Nucleic acids are large molecules that provide information to all material in the cell. 12. The four “bases” are Adenine, Guanine, Thymine, and Cytosine. They are made of Carbon,

Nitrogen, Hydrogen, and in some cases, Oxygen. 13. Crick and Watson are the two scientists who unraveled the mystery of DNA 14. A double helix is the shape of DNA. 15. A free radical is a “rebel molecule on the loose” searching for electrons, and stealing them from

stable molecules. An antioxidant is able to supply free radicals with the needed electrons to then protect the cellular molecules.

16. The special property of enzymes is the ability to break down other proteins.

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Unit 7: Unified Field Theory

Lesson 1: Astronomy

Problems 9. A planet orbits a star and is much closer to Earth. 10. Moons orbit planets. 11. A comet is a snowball in space, traveling around the Sun. A meteor is a flash of light, made by a

falling meteorite, while rushing through the air in flight, and is usually seen at night; aka “shooting star” or “falling star.” Asteroids are minor planets that never became major planets.

12. There are 9 major planets, MVEMJSUNP 13. Our galaxy is called the Milky Way. 14. There are about 400 billion stars are in our galaxy. 15. The name of a star that shrinks until it vanishes is a black hole. 16. The name of the galaxy-like nucleus at the edge of the universe is a quasar. Lesson 2: Geology Problems 8. The word “geology” means “study of the Earth.” 9. The mapmaker and famous discoverer was Christopher Columbus. 10. The GeoChemical Rock Cycle is: magma to lava to igneous to sedimentary to metamorphic to

magma. 11. The layers of the Earth’s interior are, from top to bottom: crust, upper mantle, lower mantle, outer

core, inner core. 12. A tsunami is a large wall of water caused by an earthquake beneath the floor of an ocean.

Sometimes called a “tidal wave.” 13. The three regions of Earth that have the greatest earthquake activity are Turkey, Chile, and

Southern California. 14. The rotation of Earth’s outer liquid core causes magnetic field. Lesson 3: Meteorology Problems 1. The job title of a person who studies meteorology is a meteorologist. 2. The job title of a person who studies meteorites is a meteoriticist. 3. The six lowest levels of Earth’s atmosphere are: troposphere, tropopause, stratosphere,

mesosphere, mesopause, and ionosphere. 4. The 4 main cloud types are high, middle, low, and vertical. 5. Climate can be classified as a function of temperature or precipitation. The subcategories regarding

temperature are: a. Tropical b. Subtropical c. Temperate d. Cold e. Polar

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The subcategories regarding precipitation are: 9. Equatorial 10. Tropical 11. Semiarid Tropical 12. Arid 13. Dry Mediterranean 14. Mediterranean 15. Temperate 16. Polar

Lesson 4: Unified Field Theory Problems 6. A field is any space or volume in which there is a value at any point. 7. Maxwell developed 4 laws. Briefly, they are

1. electricity can cause magnetism 2. magnetism can cause electricity 3. electricity is caused by something (electrons) 4. magnetism can’t be stored, and there are no “magnetons”

8. The Unified Field Theory is one explanation to all formulas and equations. 9. This theory is called “Unified” because it would bring together all the other laws. 10. It is called a “theory” as it has not been proven in all cases yet, but if and when it can be, it will be

a “law.”

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APPENDIX 4

Great Scientists, Thinkers and Geniuses of Physical Science

Aristotle (384 – 322 BC): Greek thinker who developed two of the three laws of

motion

Brahe (1546-1601) Danish astronomer

Celsius (1701 – 1744) Swedish Astronomer; developed temperature scale

Copernicus (1473 – 1543) Polish intellectual; mapmaker and adventurer

Crick (1916 - 2004) British Physicist; co-discovered DNA

Da Vinci (1452 – 1519) Italian inventor and painter

Einstein (1879 – 1955) German discoverer of Relativity

Fahrenheit (1686 – 1736) German who developed a temperature scale

Galileo (1564 – 1642) Italian astronomer; developed two of the three laws of

motion

Gell-Mann (1929 - ) American, postulated quarks

Hertz (1857 – 1894) German who studied light

Kelvin (1824 – 1907) Briton who developed temperature scale

Kepler (1571 – 1630) German who discovered the 3 laws of planetarium motion

Maxwell (1831 – 1879) Briton who created the 4 Laws

Newton (1642 – 1727) Briton who discovered law of gravity; developed 3 laws of

motion

Planck (1858 – 1947) German who studied light frequency

Plato (428 – 347 BC) Greek thinker and astronomer

Roentgen (1845 – 1923) German who discovered x-rays

Sagan (1934 – 1996) American Astronomer

Socrates (469 – 399 BC) Greek thinker and teacher

Watson (1928 - ) American who co-discovered DNA

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