1. Investigation Three: Electromagnets, Generators, and telegraphs
Book one: energy
Investigation Three:
Electromagnets, Generators, and telegraphs

2. Focus questions How can we create an electromagnet?
How can we make an electromagnet stronger?
How can we make a telegraph?

3. Get your Plicker’s answer pages ready!
Review! Review! Review!
Get your Plicker’s answer pages ready!

4. Crane Problem

5. 1. Electromagnet -
A piece of iron that becomes a temporary magnet when electricity flows through a wire

6. A property of electric and magnetic fields that causes interactions
2. Electromagnetism -
A property of electric and magnetic
fields that causes interactions

7. 3. coil -
A series of loops

8. The material around which a coil of insulated wire is wound.
4. Core -
The material around which a coil of insulated wire is wound.

9. Electromagnet
Coils
Core

10. A device that produces electricity from magnets.
5. Generator -
A device that produces
electricity from magnets.

11. What do we use generators for?

12. 6. Telegraph - A device that uses electromagnets
to send coded messages by
opening and closing a circuit.

13. History of the Telegraph

14. A quick back-and-forth movement
7. Vibration -
A quick back-and-forth movement

15. The switch that completes the circuit in a telegraph system.
8. Key -
The switch that completes the
circuit in a telegraph system.

16. The speed in which something moves.
9. Frequency -
The speed in which something moves.

17. A set of signals that represent letters or words for sending messages.
10. code -
A set of signals that represent letters or words for sending messages.

18. Code Methods
Grid Code
Morse Code

19. Electromagnets and Generators
Experiments!
Mrs. Smith’s Room
Mr. Croft’s Room
Electromagnets and Generators
Telegraph
Messaging

20. Focus questions How can we create an electromagnet?
How can we make an electromagnet stronger?
How can we make a telegraph?