ENERGY

Mrs. Peña – 5th Grade

Essential Question: What are some forms of Energy?

–Potential –Kinetic–Mechanical–Solar–Light–Heat–Electrical–Electromagnetic

Essential Questions: What is Energy? What is the Law of Conservation of Energy?

• Energy – the ability to cause a change in matter (movement, or a change in position)

• Law of Conservation of Energy – energy can never be made or destroyed, but it can change forms

The race car is moving, so it has energy. Where does it get its energy? It can’t just make the energy it needs. This is part of the law of conservation of energy. The race car’s engine changes the energy stored in gasoline into movement. The care moves, or changes position, because one form of energy changes into another.

• Kinetic energy- is the energy of motion. If something is moving it has kinetic energy. The faster an object is moving, the more kinetic energy it has.

An airplane flying through the air has more kinetic energy than a person

riding a bicycle.

Essential Question: What is Kinetic Energy? What is Potential Energy?

DE Science Video

Potential Energy• Potential energy is the energy an object has because

of its condition or position. For example, the higher an object is, the more potential energy it has. So a ball on the roof of a building has more potential energy than a ball on your desk, because it can fall farther.

• An object can have potential and kinetic energy at the same time.

As this roller coaster car moves to the top of the hill, it gains potential energy. The higher the car rises, the more potential energy it has. When the car moves down, it has kinetic energy. As it falls, its kinetic

energy increases and its potential energy decreases.

Essential Questions: What is Kinetic Energy? What is Potential Energy?

Let’s Review:Respond in your Science Notebook:

A car is rolling down a hill. Describe the car’s potential and kinetic energy.

Mechanical energy- is the combination of all the potential and kinetic energy that something has. This is the energy we use everyday to physically move things. When you move your chair from one place to another you are using mechanical energy.

This windup toy has a key attached to a spring. When you turn the key, you wind up, or tighten, the spring, giving the toy potential energy. The tighter it is wound up the more potential energy it has stored. When the toy is moving, it has kinetic energy. Since the spring is still partly wound up, the toy also has some potential energy left. The toy’s mechanical energy is a combination of its potential energy and its kinetic energy.

Essential Question: What is Mechanical Energy?

Energy Transfer• Energy transfer- the movement of energy from

one place or object to another. o A baseball player hits a ball, kinetic energy is

transferred from the bat to the ball. o A hammer strikes a nail, kinetic energy is transferred

from the hammer to the nail. Can you think of other examples?

The boy’s kinetic energy is transferred to the spring, where it changes into potential

energy. As the spring expands, that potential energy is transferred to the boy as kinetic

energy, bouncing him into the air.

Essential Question: What is Energy Transfer?

• Chemical energy- energy stored in fuel. This is energy that can be released by a chemical reaction, such as burning or digestion. When it is not being used, it is potential energy. A chemical reaction is needed to change this potential energy into kinetic energy.

Our muscles get energy from the food we eat. The potential energy stored in food is chemical energy. When it’s released, it gives us kinetic energy to move.

Chemical energy in fuel is used to keep this remote-controlled helicopter flying in the air.

Essential Question: What are some other forms of Energy (solar, light, heat,

ultraviolet, chemical, mechanical, etc.) ?

Essential Question: What is solar Energy?

• Solar Energy- energy that comes from the sun. The word solar means “of the sun.” People use solar cells that change light energy from the sun into electricity. o Solar calculatorso Solar panels to heat swimming poolso Solar panels that provide light and power

appliances in homes or other buildings

Without solar energy, Earth would be just a ball of frozen rock with no life. The sun is the source of almost all energy on Earth. Light from the sun helps plants make food and oxygen. Its energy is stored in fossil fuels- coal, oil, and natural gas that come from long-dead plants and animals. The sun’s energy is also the source of weather.

• Other forms of energy come from the sun directly. Energy from the sun travels as radiation. The sun provides different types of radiation.

o Light, radiation we seeo Heat, radiation we feelo X rayso Ultraviolet rayso Radio waves, which we hear as static on radios *some of these rays can be dangerous

• Light is energy you can see. It moves in waves. How big those waves are determines what type and color of light it is. Those waves, however, are so small that they appear to be straight lines. The complicated part is that light moves in straight lines only when it’s not moving through anything at all (ie. in a vacuum). When it moves through air, water, glass, or anything else, its behavior changes.

Essential Questions: What is Light Energy?

Essential Questions: What is Light Energy?

There are two main things that happen to change the direction of the light’s motion:

(1) Reflection- is what happens when light bounces off of something. This is what you see when you look in the mirror. This is also what you see when you look at anything around you. In order to reach your eyes, light bounces off of the object that you’re looking at, changing its direction. It can also bounce off of particles (like water) in the air, which is why you may be able to see beams of sunlight on a foggy day.

(2) Refraction- is what happens when light passes from one medium (one type of stuff) into another. When this happens, the light will actually bend. (Actually, it usually splits in two - some of it reflects off the surface, and some of it keeps going through.) The light that goes through bends at the surface. The angle that it bends at depends on what the two mediums are. For example, light will bend a different amount when it goes from air into glass than it does when it goes from air into water

• Sound- is energy in the form of vibrations that travel through matter. Sound vibrations pass through the particles of matter in a kind of domino effect. When a vibration reaches a particle of matter, that particle starts to vibrate, too. In this way, sound vibrations can spread out, not just in a straight line, but in all directions. o Sound travels through air, so people can hear sounds-even quiet ones-at

a distanceo You can place your hands on a radio or TV and feel the sound vibrations.o Some people with hearing disabilities have been able to become dancers

by feeling the vibrations of the music through their feet. o Sometimes you can feel sound, like at a fireworks show. Many fireworks

produce not only bright colors, but also loud whistles, pops, and bangs. You can often feel the energy of these sounds on your body.

Essential Question: What is Sound Energy?

• Electricity, or electric energy- energy that comes from an electric current. An electric current results from the movement of electrons. Electrons are particles found in atoms. You can see some effects of electric energy when you use appliances. You may have even felt electric energy. Have you ever walked across a rug on a dry day and then touched a doorknob? You probably felt electric energy in the form of a small shock (static electricity orelectricity that is not moving).

Essential Question: What is Electricity?

Essential Question: How is Heat Transferred?

• All matter is made up of tiny particles that are always moving. Since they move, they have kinetic energy, also called thermal energy.

• Heat- is the transfer of thermal energy between objects with different temperatures.

• Thermal energy travels from a warmer object to a cooler object.

Energy from the stove burner flows through the pot and into the water, causing it to get hot. Energy doesn’t travel from the low-temperature water to the high-temperature burner.

Essential Question: What is Temperature?

• Temperature- is the measurement of the average kinetic energy of all the particles in a substance. You can measure temperature with a thermometer. The number shown on a thermometer is related to the amount of kinetic energy in a substance.

• Some systems are very efficient at transferring thermal energy. A System is a set of parts acting together as a whole object.

A burner, a pot, and water are a system through which Thermal energy moves. The burner transfers thermalEnergy to the pot. The pot transfers thermal energy toThe water. As the water receives more and more Thermal energy, its particles move faster.

Essential Question: What is Thermal Energy Transfer?

• Conduction- the transfer of thermal energy from one object directly into another (heat from the iron moves directly into the clothing)

• Convection- the transfer of thermal energy through the movement of a gas or a liquid. As a gas or liquid is heated, the heat causes it to move upward, carrying heat to the area above the heat source (heated air moves up, carrying thermal energy to the air above it)

• Radiation- the transfer of energy by waves that move through matter and space. Not all radiation from the sun reaches Earth’s surface. Some of it is reflected back into space by the atmosphere. Reflection occurs when heat or light bounces off an object. (Radiation carries thermal

      energy from the lamp to the food)

There are three ways heat can move through a system.

Directly from handle to handThrough the movement of water

By the heat waves emitted from the

fire

Essential Question: What are Insulators and Conductors?

Insulator- anything that slows the movement of thermal energy (coolers, Styrofoam cups, fur coat)

Conductors- anything that allows thermal energy to move through it easily (most metals).

The lunch bag prevents heat in the air from movingInto the bag. This keeps the food in the bag cool.

The cookie sheet is a conductor. The oven mitt is an insulator.

Essential Question: What is an Electrical Circuit?

In order for electricity to work, there needs to be something called a complete circuit. In a complete circuit, energy moves in a circle. It starts out in one place, travels around the circuit, and moves back to the place where it originated. A battery is a good example of how complete circuits work. Batteries are devices that produce electricity by changing stored chemical energy into electrical energy. A chemical reaction inside a battery creates electrons. Once created, the electrons are stored in one end of the battery, called the negative terminal, usually denoted by a “–” sign. When a battery is plugged into a device that needs it, the electrons travel from the negative terminal to the positive terminal, usually denoted by a “+” sign. Batteries can be used to power tiny things like hearing aids or large things like cars.

Complete CircuitsComplete Circuits

Circuits need to be complete in order for them to work properly.

This means that the wires must go in a full loop around from the power source and back again

Circuits that are not complete, WILL NOT WORK!

Essential Question: What is Electromagnetism?

• Electromagnetism -works on the principle that an electric current through a wire generates a magnetic field. This magnetic field is the same force that makes metal objects stick to permanent magnets. In a bar magnet, the magnetic field runs from the north to the south pole. In a wire, the magnetic field forms around the wire. If we wrap that wire around a metal object, we can often magnetize that object. In this way, we can create an electromagnet.

Electromagnets are a part of our everyday lives. Theyare useful because they act like magnets when the current is on and lose their magnetism when the current is off. Some electromagnets we use everyday are in school bells, telephones, automatic doors and tape recorders

Essential Questions: What are renewable and non-renewable resources? How do people use energy?

• Nonrenewable energy Resourceso Fossil fuels- the remains or traces of past life found in

sedimentary rock. Fossil fuels are fuels that formed from the remains of once living things, for example coal, oil, an natural gas.

o It takes millions of years for coal, oil, and natural gas to form. When supplies are used up, there will be no more. This is why coal, oil, and natural gas are called nonrenewable resources. These materials, once used up, cannot be replaced within a reasonable amount of time.

o Conservation- using less of something to make the supply last longer

• Renewable resource- a resource that can be replaced within a reasonable amount of time, for example solar energy (sun), hydroelectric energy (water), and wind energy

Essential Questions: What are renewable and non-renewable resources? How do people

use energy?

Essential Questions: How can you help the Environment?

• There is a great deal of information to process in this unit.. Please make sure study nightly. Don’t wait until the last minute to begin studying for the test.

• I am available to answer questions and help you with any concept you don’t understand. You can come as early as 7:40 a.m.

Happy Studying ☺