Electric Circuits

By: ________ 4-__

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Table of Contents1. Cover Page2. Table of Contents3. Electric Safety Rules Contract4. Thinking About Electricity and Its Properties5. What Electricity Can Do?6. Experiment 1 – Hypotheses7. Experiment 1 – Test Your Hypotheses8. Experiment 1 – Results9. Parts of a Light-Bulb10. Experiment 2 – The Light-Bulb11. Test Circuits12. What’s wrong with the circuit?13. Experiment 3 – Conductors and Insulators14. Experiment 3 – Conductors and Insulators15. Experiment 4 – Making a Filament16. Experiment 5 – Hidden Circuits17. Experiment 6 – Deciphering a Secret Language18. Creating a Circuit Diagram19. Exploring Series and Parallel Circuits20. Exploring Series and Parallel Circuits21. Vocabulary22. Vocabulary23. Vocabulary

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Electric Safety Rules Contract

I, ____________________ promise to…

1.Never experiment with the electricity in wall plugs! Both of these currents can give a lethal shock!

2.Remember that electrical appliances that operate on household electricity can deliver shocks.

3.Avoid downed power lines and electrical substations. They can also give deadly shocks.

Signature Date

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Thinking About Electricity and Its Properties

Just a mere 200 years ago, electricity had not yet been discovered. Life was very different back then. People lit their homes with candles or whale oil. They sent messages by word of mouth and letters by foot, horse, or boat.

In 1752, Benjamin Franklin paved the way for an understanding of electricity with his famous experiments. He revealed that lightning was electricity. In the early 1800s, Michael Faraday added to this knowledge by discovering the relationship between magnetism and electricity. In the mid-1800s, Joseph Henry revealed the nature of electromagnetic induction. The foundation was then laid for a score of inventions, from the light-bulb by Thomas Edison to the telegraph by Samuel Morse. Today, we continue to add to the list of inventions that depend on electricity.

Important People1.________________________ discovered that lightning

was electricity.2.________________________ discovered that magnetism

and electricity were related. 3.The light-bulb was invented by

________________________.4.________________________ created the telegraph,

which relayed messages.

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What Can Electricity DoToday, you will discover how to light a bulb using a simple battery, piece of wire, and small light-bulb.

Electricity flows through a path called a ____________.

A _______________ acts as the source for energy. Each battery has a positive (+) and a negative (-).

The positive end has a small, raised button on it; the negative end is flat.

Materials can be roughly divided into two groups: ________________ & ________________.

Conductors allow the flow of electricity.

Insulators will not allow the flow of significant amounts of electricity. To prevent shocks, the wire is covered by a plastic or rubber covering that acts as an insulator.

The circuit is established when there is a continuous path for electricity to travel from one end of the battery back to the end.

There are at least four ways using one wire, one bulb, and one battery to light your bulb. Turn to the next page to make your hypotheses on which methods will work.

A _____________ circuit will allow electricity to flow. An _____________ circuit will not allow electricity to flow.

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Experiment 1 – HypothesesWrite ON above each “hypothesis” if you think the configuration will make your bulb light. Write OFF if you think the bulb will not light.

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Experiment 1 – Test

Now, you are ready to test your hypotheses. Below write ON above “Result” if your test made your bulb light. Write OFF if the test did not allow the bulb to light. Compare your hypotheses and results with some other groups. If you finish early, see if you can try any other methods for lighting the bulb.

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Experiment 1 – Results

In the boxes below, draw 4 combinations that allowed your bulb to light. Use the symbols from page 6.

1.Why did these four combinations allow the bulb to light? (Hint: They all have something in common)____________________________________________________________________________________________________________________________________________________________________________________________________________

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Parts of a Light-Bulb

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Experiment 2 – The Light-Bulb

1.Question: How many batteries do you think it will take to light the bulb. _______ batteries

2.Hypothesis: How do you think the standard light-bulb can be lit using D-cell batteries and wires? Draw a diagram below.

3.Results: How many batteries did it take to light the standard bulb? _______ batteries

4.Check your hypothesis! – Was your hypothesis correct? _______. Why or why not? _______________________________________________________________________________________________________________________

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Test Circuits

Make your hypotheses for each combination. Test each hypothesis using one wire, one bulb, and one battery.

Number Correct /6

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What is wrong with the Circuit?

What is the problem with diagram 1? ______________________________________________________________________________________________________________

What is the problem with diagram 2?______________________________________________________________________________________________________________

For diagrams 3 and 4, complete the diagram by drawing the other half of the wires connected in a way that will complete the circuit and make the bulb light. *If you finish, grab a bulb, 2 wires, 1 battery, 1 bulb socket, and 1 battery holder. Practice wiring your circuits!

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Experiment 3 – Conductors and Insulators

Background: Conductors and insulators are important components in electric circuits. Conductors are materials through which electricity can travel. Insulators, on the other hand, are materials through which electricity cannot travel.

To determine if a material is a conductor or insulator, place the material between the two wires of the circuit tester. The picture below shows how to use the circuit tester to see if an object can be part of a circuit. If the bulb lights, you will know that the material conducts electricity.

Turn the page to try your next experiment!

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Experiment 3 – Conductors and Insulators

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Making a Filament

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Hidden Circuits

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Deciphering a Secret Language

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Creating a Circuit Diagram

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Exploring Series and Parallel Circuits

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Exploring Series and Parallel Circuits

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VocabularyAtom _______________________________________________________

Attract _______________________________________________________

Battery _______________________________________________________

Battery terminal ______________________________________________________________________________________________________________

Circuit _______________________________________________________

Conductor _______________________________________________________

Discharge _______________________________________________________

Electrical energy ______________________________________________________________________________________________________________

Electric charge______________________________________________________________________________________________________________

Electric current______________________________________________________________________________________________________________

Electricity_______________________________________________________

Electric motor_______________________________________________________

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Electromagnet______________________________________________________________________________________________________________

Energy_______________________________________________________

Filament_______________________________________________________

Generator_______________________________________________________

Insulator_______________________________________________________

Magnet_______________________________________________________

Magnetic field_______________________________________________________

Magnetic Poles_______________________________________________________

Magnetism_______________________________________________________

Open circuit______________________________________________________________________________________________________________

Parallel circuit ______________________________________________________________________________________________________________

Repel _______________________________________________________

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Resistance_______________________________________________________

Series circuit______________________________________________________________________________________________________________

Static electricity _______________________________________________________

Switch_______________________________________________________

Volt_______________________________________________________

Voltage_______________________________________________________

Watt_______________________________________________________

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