Electrical energy (dherich pascual)

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Objectives:

1. Define electricity.

2. Identify the process of creating device that measures electricity.

3. Identify sources of electricity.navigate quicklynavigate quicklyLesson properLesson proper


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Objectives

Introduction

Experiment (galvanometer)

Experiment (sources of electricity(

Test



Objectives

Introduction

Experiment (galvanometer)

Experiment (sources of electricity(

TestHOMEHOME

Introduction

Scientist have found out a great deal- but not everything- about electricity.

Electricity, one of the basic forms of energy. Electricity is associated with electric charge, a property of certain elementary particles such as electrons and protons, two of the basic particles that make up the atoms of all ordinary matter. Electric charges can be stationary, as in static electricity, or moving, as in an electric current.



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Electricity is an extremely versatile form of energy. It can be generated in many ways and from many different sources. It can be sent almost instantaneously over long distances.

Electricity can also be converted efficiently into other forms of energy, and it can be stored. Because of this versatility, electricity plays a part in nearly every aspect of modern technology.

Electricity provides light, heat, and mechanical power. It makes telephones, computers, televisions, and countless other necessities and luxuries possible.



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You know that everything is composed of tiny particles called atoms. There are over a hundred different kinds, but all are alike in two ways.

1. Every atom is composed of a central portion called a nucleus. 2. Every atom has one or more electrons whirling around the nucleus.

Ordinary electrons stay in their own paths, but they can be forced out. They can be made to move in a stream. Such a stream of electrons is called an electric current.

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Uhm. . Wait , my problem is. . . .

how can I determine the presence of

electric current?

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I guess this would be of great help! !

Galvanometer! ! !

Click here to continue

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Galvanometer???.

What is that?. I hadn’t even hear

that before.


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Galvanometer is an instrument used to measure small amount of electric current.


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I thought it is expensive, i don’t

have enough money for it!


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Nope! You can do it by your

self

But how?




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Well, try this activity.. And

good luck!

Ok , I’ll try it.



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EXPERIMENT

MAKING A GALVANOMETER

You will need a coil of insulated wire, a compass, plastic tape, and milk cartoon.Direction:

1. Cut away the base of the milk carton including 1 inch of sides. Then cut a slot in the base as shown.




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2. Wind 20 turns of wire in a coil about as big as the compass.

3. Flatten the coil and attach it to the compass with plastic tape.

4. Lay the coil and compass across the slot. Let the two ends of the wire come out through two holes in the side.




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Now your galvanometer is ready.



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Electric Current from Chemical Change



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You know that a flashlight cell contains chemicals. When you connect a bulb to it, a chemical change takes place, an electric current is produces, and the bulb lights.



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Yup, you’re right! ! !Actually every chemical change is accompanied

by a movement of electrons-an electric

current. But we choose certain chemicals because they give

strong flow than others.



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Are there simple materials for that

electricity?



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Wanna try this activity?

Well, I guess!



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Experiment

Electric Current from Chemical ChangeMaterials:

galvanometersmall piece of aluminum foilsmall piece of tin-canpennynickeldimeiron washerzinc coated washerblotting paperglass of salt water



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Procedure1. Shine each piece of metal with steel wool or scouring

powder. Dip a piece of blotting paper in salt water. Then use it as the “filling” of a sandwich. The “bread” of the sandwich is the penny and zinc-coated washer.

Now you have a chemical source of electricity, an electric cell. It consists of two different metals – copper and zinc – and a liquid – salt water – which acts chemically on them and conducts electricity. A liquid that conducts electricity is called an electrolyte.



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2. Test the current given off by your cell. Place your galvanometer in the table and turn it until the compass needle is in line with the coil. Then press one of the wires into the penny and the other wire onto the washer. Then observe.



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3. Now try all the other “sandwich” combinations – dime and penny, dime and aluminum, zinc and aluminum, etc. in each case use the blotter and salt water electrolyte between. Keep a record of your results. Which combinations gives the strongest current?



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TEST YOUR SELF



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Direction: Click the letter that corresponds to your answer.

Which of the following is possible source of electricity?

A. chemical reactions

B. generators

C. battery

D. all of the above

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Which of the following tells about electron?

A. a negative charge particle in an atom

B. the neutral charge in atom particle

C. the particle of atom in positive charge]

D. the flow of electric charge

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Salt is one source to produce electricity. Why does the salt solution not present in a flashlight cell?

A. It is rare in nature

B. It produce small amount of electricity

C. It is much heavier than the other chemical

D. It is much expensive

End of test

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wrong ! ! ! !

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electrons Electron, negatively charged p

article found in an atom. Electrons, along with neutrons and protons, comprise the basic building blocks of all atoms. The electrons form the outer layer or layers of an atom, while the neutrons and protons make up the nucleus, or core, of the atom. Electrons, neutrons, and protons are elementary particles—that is, they are among the smallest parts of matter that scientists

can isolate. Microsoft ® Encarta ® 2008. © 1993-

2007 Microsoft Corporation. All rights reserved.

proton

elementary particle that carries a positive electric charge and, along with the electron and the neutron, is one of the building

blocks of all atoms. Microsoft ® Encarta ® 2008. © 1993-2007 Microsoft Corporation. All rights reserved.

nucleus in atomic structure, the positively charged

central mass of an atom about which the orbital electrons revolve. The nucleus is composed of nucleons, that is, protons and neutrons, and its mass accounts for nearly the entire mass of the atom.

Electric Current Flow of electric charge. The electric charge in a current is

carried by minute particles called electrons that orbit the nuclei of atoms. Each electron carries a small electric charge. When a stream of electrons moves from atom to atom—for example, inside a copper wire—the flow of the charge they carry is called electric current. Batteries and generators are devices that produce electric current to power lights and other appliances. Electric currents also occur in nature—lightning being a dramatic example.

Electric currents flow because atoms and molecules contain two types of electrical charge, positive and negative, and these opposite charges attract each other. If there is a difference in the overall charge of atoms between two points—for example, between two ends of a wire—the negatively charged electrons will flow toward the positively charged end of the wire, creating electric current. Direct current (DC) is the flow of electricity in one direction. Alternating current (AC) intermittently reverses direction because of the way it is generated.

Microsoft ® Encarta ® 2008. © 1993-2007 Microsoft Corporation. All rights reserved.

Dry Cell Battery

This simple dry cell battery contains a negative electrode (a zinc sheath which encloses the battery materials) and a positive electrode (the carbon rod and the carbon and manganese dioxide mixture that surrounds the rod). An electrolyte paste separates the two electrodes and facilitates a chemical reaction between them. This reaction causes a current to flow (that is, makes the electrons move) through a conductor that connects the positive and negative electrodes.

Microsoft ® Encarta ® 2008. © 1993-2007 Microsoft Corporation. All rights reserved.

Salt and water may not only be separated when in solution, but each may be broken down into other substances. This, however, involves a different kind of change—one that usually requires more energy than a physical change and that alters the fundamental nature of the material. This type of change is called a chemical change. Microsoft ® Encarta ® 2008. © 1993-2007 Microsoft

Corporation. All rights reserved.

Zinc bluish-white

metallic element that has many industrial applications. Zinc is one of the transition elements of the periodic table Microsoft

® Encarta ® 2008. © 1993-2007 Microsoft Corporation. All rights reserved.

copper

Two important kinds of copper ore are contained in this sample: chalcopyrite (top) and bornite (bottom). Copper ore is found throughout the world, but the low percentage of metal obtained from the ore and the often hard-to-access location of deposits make many potential mines uneconomic. Copper is the second most-used metal in the world and is valued for its conductivity, malleability, resistance to corrosion, and beauty. Microsoft ® Encarta ® 2008. © 1993-2007 Microsoft Corporation. All rights reserved.

Solutions of ions conduct an electric current, in much the same manner as a wire does. Ions can move about in a solution and carry a charge, just as electrons moving along a wire conduct a current. Substances that can carry a charge through solution in this way are called electrolytes; those that cannot are called nonelectrolytes. Microsoft ®

Encarta ® 2008. © 1993-2007 Microsoft Corporation. All rights reserved.

Electrical energy (dherich pascual)

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