1. Unit 4 Electricity and Magnetism
Study Guide
Unit 4 Electricity and Magnetism

2. What happens when you move a wire within a magnetic field?
an electric current is created

3. 2. How do you create an electromagnet?
wrap a coil of wire around a soft iron core and attaching it to a battery

4. 3. What is a solenoid?
A coil of copper wire attached to a battery

5. 4. What can you do to increase the strength of an electromagnet (the solenoid’s magnetic field)?
Add more turns to the coil
Add/increase the iron core
increase the current flowing through the coil (add more batteries)

6. How can you increase the brightness of lights in a simple series circuit?
Add more batteries

7. 6. To test how the amount of electric energy delivered to a motor affects its speed you would measure
the rotations per second of a motor when it is connected to one battery, two batteries and three batteries

8. 7. When a copper wire is placed within a magnetic field, what must happen for electric current to be generated in the wire?
The wire must be moving relative to the magnetic field

9. 8. Turning the handle of a hand generator creates an electric current that lights a light bulb. What does the handle do?
It moves a magnet

10. 9. What happens to the magnitude of the force exerted by two magnets on each other as the distance between the two magnets changes?
The closer the magnets are to each other, the greater the force.

11. 10. What is happening inside an electric generator enabling it to generate an electric current?
a magnet is being moved

12. 11. An electric current generates a
magnetic field.

13. 12. What is an electric motor?
a machine that converts energy from electricity into mechanical energy

14. 12. What is a generator?
machine that converts energy from mechanical energy into electricity

15. 14. What is weight?

16. Gravity depends on what two factors?
Objects with more mass exert more gravity.
17. As distance increases gravity decreases.

17. 18. What force gives atoms their structure?

18. What has to be aligned within an object to make it magnetic?
domains

19. What is a magnet?
Any material that attracts iron or materials containing iron

20. In what method of charging does an uncharged object become charged without direct contact?

24. 22. Describe a situation where an object is charged through friction then charges another through induction.

25. 23. Classify as conductor or insulator:
Rubber
Insulator
Wood
Insulator
Copper
conductor
Plastic
Insulator

26. Distribution of charge determines if a material is an insulator or conductor. How do insulators and conductors differ?
In how well they allow electrons to flow

27. 25. How are charges distributed on conductors (conductive material)?

28. How are charges distributed on insulators?
Charges will be unevenly distributed

29. 27. What happens when a neutral object approaches a positively charged object?
Negative charges will move from the neutral object to the positively charged object