Name______Team______Period____

Creating Electricity From Magnetism

  1. Station #1. Electromagnetic Induction (page 72-73)

a.Move a bar magnet in and out of a coil of wire which is attached to a device which can detect an electric current. Notice the needle on the galvanometer. Record your observations.

b.Repeat the activity using the opposite pole of the magnet. How is the needle reading different this time?

c.Hold the magnet inside the coil of wire. If you do not move the magnet, does electricity flow through the wire?

d.Predict what will happen if you hold the magnet steady and move the coil back and forth.

e.Check your prediction in part (d).

f.Describe what you have to do to make the reading on the galvanometer as large as possible.

  1. Make a generalization about inducing an electric current with a magnetic field.
  1. Station #2. Try to induce a current in a coil of wire by moving it inside a horseshoe magnet. (See the diagram on page 74.) What factors affect the direction of the induced current?
  1. If you rotate a wire loop through a horseshoe magnet, why does the direction of the induced current alternate? (See diagram on page 75.)
  1. What is meant by the term generator? (pages 74-77)
  1. Is the current produced by dry cells direct current or alternating current? How can you tell?
  1. Is the current that you get from a wall outlet direct current or alternating current?
  1. Why do power companies send alternating current to your home instead of direct current?
  1. How do power plants get the energy required to turn the wire loops in their generators?
  1. Station #3. Operate the dynamo flashlight.
  1. Why doesn’t it need batteries?
  1. Carefully observe the dynamo flashlight and see if you can explain how it works. You may want to look at the dissected one to help you figure out the parts to it.
  1. Station #4. Hook up a Genecon to a light bulb in a holder.

a.Gently crank the Genecon to produce enough electricity to light a bulb. Draw a picture of the flow of electricity through your circuit.

b.What do you think will happen if you switch the leads around?

c.Check out your prediction from part (b).

d.When you use the Genecon to light a light bulb, are you using it as a generator or as a motor? How can you tell?

  1. Station #5. Attach the leads of a Genecon to a dry cell and watch the handle.

a.Record your observations.

b.What type of energy is being converted into what type of energy?

c.Predict what will happen if you switch the leads around.

d.Check out your prediction in part (c).

e.Is the Genecon acting as a generator or a motor? How can you tell?

  1. Station #5. This time you are going to hook up the Genecon to two dry cells hooked up in series.

a.Predict what will happen.

b.Check out your prediction in part (a). Compare the results to the motion of the Genecon in #11.

c.Draw a diagram of the circuit showing the flow of electricity.

13.Station #5. Hook up two dry cells in parallel and then connect them to a Genecon.

a.How does the motion compare to #12? Why?

b.Draw a diagram of the circuit showing the flow of electricity.

14.Station #6. Attach the leads of Genecon A to the leads of Genecon B.

  1. Gently crank the handle of Genecon A and watch the handle of Genecon B. Record your observations.
  1. What type of energy is being converted into what type of energy in part (a)?
  1. How far did the handle of Genecon B turn when Genecon A made one complete turn?
  1. Is the transference of energy from Genecon A to Genecon B 100% efficient? Justify your response.
  1. Only part of the energy that you put into Genecon A went into Genecon B. Where did the rest of the energy go?
  1. Was Genecon A acting as a generator or a motor in this activity? How can you tell?
  1. Was Genecon B acting as a generator or a motor in this activity? How can you tell?

15.Station #7. Let’s explore an Edy current.

a.Is copper magnetic? Be sure to test it.

b.Drop each weight through the copper tube. Try to explain why they behave differently.

c.How would each weight behave it were dropped through a plastic tube? Why?

16.Explain how information is stored on a videotape. (pages77-78)

17.Explain how the information on a videotape is read. (pages 77-78)

18.How do power plants increase the voltage of the power produced by their generators? Draw a picture to help with your explanation. (pages 78-80)

19.How is the high voltage of the power lines reduced before it enters your home? Draw a picture to help with your explanation. (pages 78-80)

20.Summarize:

a.Give examples of how electricity can be created from magnets and magnetic fields.

b.Give examples of how magnets and magnetic fields can be created from electricity.