1. Magnets Review

2. The region around a magnet in which magnetic forces can act is called the
Magnetic field
Domain
Pole
solenoid

3. A)Magnetic field

4. The marked end of a compass needle always points directly to
A) earth’s geographic south pole
B) earth’s geographic north pole
C) magnet’s south pole
D) magnet’s north pole

5. B) earth’s geographic north pole

6. What do you end up with if you cut a magnet in half?
One north-pole piece and one south-pole piece
two unmagnetized pieces
Two pieces, each with north and south pole
Two north pole pieces

7. C) Two pieces, each with north and south pole

8. Earth’s magnetic field
Is produced by a giant magnet at the center of the Earth
Is produced by movement of electric charges in Earth’s core
Does not change over time
Bends outward at the magnetic poles

9. b)Is produced by movement of electric charges in Earth’s core

10. Which of the following is NOT true about an electromagnet?
It can be strong enough to levitate a train
The current may be turned on or off
Its strength is reduced by adding more loops
It consists of an iron core and current-carrying wire

11. c)Its strength is reduced by adding more loops

12. Any material that attracts iron or materials containing iron is called
Solenoid
Magnet
Superconductor
semiconductor

13. b) Magnet

14. All magnets
a) have two poles
b) Exert forces
c) Are surrounded by a magnetic field
d) All of the above

15. d) All of the above

16. The magnetic effects of a bar magnet are
Evenly distributed throughout a magnet
Distributed randomly in a magnet
Concentrated near the ends
None of the above

17. c) Concentrated near the ends

18. Sometimes the magnetic strip on a credit card becomes demagnetized
Sometimes the magnetic strip on a credit card becomes demagnetized. The strip is most likely a
Permanent magnet
Temporary magnet
Electromagnet
geomagnet

19. b)Temporary magnet

20. If you attach a magnet to a string so that the magnet is see to rotate, you will see that one end of the magnet will point
North
Southwest
East
west

21. a) North

22. The Earth has neither an east pole nor west pole because
a)The earth is a sphere and has no poles
b) The earth is a sphere and has only one pole called an axis
c) The earth is like a bar magnet, which has two poles
d) None of the above

23. c) The earth is like a bar magnet, which has two poles

24. A compass needle is
A fixed magnet
A fixed nonmagnetic piece of metal
A magnet that is free to rotate
A nonmagnetic piece of metal that is free to rotate

25. C) A magnet that is free to rotate

26. Magnetic poles always occur
Alone
In pairs
In threes
In fours

27. B) In pairs

28. The magnetic force will pull magnets apart if you hold the
North poles of two magnets together
South poles of two magnets together
North pole of one magnet near the south pole of another magnet
Both A and B

29. d)Both A and B

30. The magnetic force will pull magnets together if you hold the
North poles of two magnets together
South poles of two magnets together
North pole of one magnet near the south pole of another magnet
Both A and B

31. C) North pole of one magnet near the south pole of another magnet

32. Magnetic poles are similar to electric charges in that
Like poles repels and opposite poles attract
The magnetic force is equal to the electric force
The number of magnetic domains responsible for the poles is conserved.
The mass of magnetized particle is conserved

33. A) Like poles repels and opposite poles attract

34. The magnetic field around a bar magnet can be modeled by drawing
Curved lines from the north pole of the magnet to the south pole
Curved lines near the south pole of the magnet
Straight lines from the north pole and from the south pole
Circular lines around the entire magnet

35. A) Curved lines from the north pole of the magnet to the south pole

36. Whether a material is magnetic depends on _____ in the material
Molecules
Atoms
Number of neutrons
Number of protons

37. B) Atoms

38. A magnet can be demagnetize if
a) it is dropped
b) it is heated
c)it is stuck very hard
d) all of the above

39. d) all of the above

40. A magnet, usually within an iron core, produced by an electric current is
Electromagnet
Ferromagnet
Temporary magnet
Permanent magnet

41. A) Electromagnet

42. Turbines generally turn the _______ in a generator, inducing an electric current
Transformer
Magnet
Wire loop
solenoid

43. B) Magnet

44. Which of the following is currently being used to turn turbines in generators?
a) steam
b) water
c) wind
d) all of the above

45. d) all of the above

46. The interaction between electricity and magnetism is called
a) electromagnetism
b) Electromagnetic induction

47. a) electromagnetism