1. Prepared by Dedra Demaree, Georgetown University
Magnetism
Prepared by
Dedra Demaree, Georgetown University
© 2014 Pearson Education, Inc.

2. Voting question If you split a magnet in half, you will have:
One half that is a north pole and one half that is a south pole.
Two halves that are both north poles.
Two halves that are both south poles.
Answer: A) One half that is a north pole and one half that is a south pole.
© 2014 Pearson Education, Inc.

3. Voting question If you split a magnet in half, you will have:
One half that is a north pole and one half that is a south pole.
Two halves that are both north poles.
Two halves that are both south poles.
Answer: A) One half that is a north pole and one half that is a south pole.
© 2014 Pearson Education, Inc.

4. Voting question Earth's geographic north pole is:
A magnetic north pole.
A magnetic south pole.
Not a magnetic pole.
Answer: B) A magnetic south pole.
© 2014 Pearson Education, Inc.

5. Voting question Earth's geographic north pole is:
A magnetic north pole.
A magnetic south pole.
Not a magnetic pole.
Answer: B) A magnetic south pole.
© 2014 Pearson Education, Inc.

6. Voting question
When the south pole of the bar magnet is brought closer to the compass, the compass needle will:
Not rotate.
Rotate so that its south pole is closer to the south pole of the bar magnet.
Rotate so that its north pole is closer to the south pole of the bar magnet.
Answer: C) Rotate so that its north pole is closer to the south pole of the bar magnet.
© 2014 Pearson Education, Inc.

7. Voting question
When the south pole of the bar magnet is brought closer to the compass, the compass needle will:
Not rotate.
Rotate so that its south pole is closer to the south pole of the bar magnet.
Rotate so that its north pole is closer to the south pole of the bar magnet.
Answer: C) Rotate so that its north pole is closer to the south pole of the bar magnet.
© 2014 Pearson Education, Inc.

8. Voting question The compasses in the figure indicate that:
The magnetic field lines between the ends of the horseshoe magnet point from south to north.
The magnetic field lines between the ends of the horseshoe magnet point from north to south.
The magnetic field lines between the ends of the horseshoe magnet point straight up.
Answer: B) The magnetic field lines between the ends of the horseshoe magnet point from north to south.
© 2014 Pearson Education, Inc.

9. Voting question The compasses in the figure indicate that:
The magnetic field lines between the ends of the horseshoe magnet point from south to north.
The magnetic field lines between the ends of the horseshoe magnet point from north to south.
The magnetic field lines between the ends of the horseshoe magnet point straight up.
Answer: B) The magnetic field lines between the ends of the horseshoe magnet point from north to south.
© 2014 Pearson Education, Inc.

10. Voting question
A compass needle rotating near a current-carrying wire is evidence that:
The current produces an electric field.
The current produces a magnetic field.
Both of the above.
Neither of the above.
Answer: B) The current produces a magnetic field.
© 2014 Pearson Education, Inc.

11. Voting question
A compass needle rotating near a current-carrying wire is evidence that:
The current produces an electric field.
The current produces a magnetic field.
Both of the above.
Neither of the above.
Answer: B) The current produces a magnetic field.
© 2014 Pearson Education, Inc.

12. Voting question
For a horizontal current-carrying wire with current to the right, use the right-hand rule to determine the direction of the magnetic field above the wire.
The magnetic field points to the right.
The magnetic field points to the left.
The magnetic field points into the page.
The magnetic field points out of the page.
Answer: D) The magnetic field points out of the page.
© 2014 Pearson Education, Inc.

13. Voting question
For a horizontal current-carrying wire with current to the right, use the right-hand rule to determine the direction of the magnetic field above the wire.
The magnetic field points to the right.
The magnetic field points to the left.
The magnetic field points into the page.
The magnetic field points out of the page.
Answer: D) The magnetic field points out of the page.
© 2014 Pearson Education, Inc.

14. Voting question
Using the right-hand rule for the magnetic force, determine the direction of the force on a current-carrying wire in the following situation. The current is upward; the magnetic field is out of the page. The force is:
Upward.
Out of the page.
To the right.
To the left.
Answer: C) To the right.
© 2014 Pearson Education, Inc.

15. Voting question
Using the right-hand rule for the magnetic force, determine the direction of the force on a current-carrying wire in the following situation. The current is upward; the magnetic field is out of the page. The force is:
Upward.
Out of the page.
To the right.
To the left.
Answer: C) To the right.
© 2014 Pearson Education, Inc.

16. Voting question
A current flows to the left in a wire that is just above another wire with a current that flows to the right. Which of the following statements is correct?
The wires will attract each other.
The wires will repel each other.
The wires will not interact.
The wires will rotate.
Answer: B) The wires will repel each other.
© 2014 Pearson Education, Inc.

17. Voting question
A current flows to the left in a wire that is just above another wire with a current that flows to the right. Which of the following statements is correct?
The wires will attract each other.
The wires will repel each other.
The wires will not interact.
The wires will rotate.
Answer: B) The wires will repel each other.
© 2014 Pearson Education, Inc.

18. Voting question The magnetic force exerted on a current:
Increases with the strength of the current.
Increases with the length of the current-carrying wire.
Increases with the strength of the magnetic field.
All of the above.
None of the above.
Answer: D) All of the above.
© 2014 Pearson Education, Inc.

19. Voting question The magnetic force exerted on a current:
Increases with the strength of the current.
Increases with the length of the current-carrying wire.
Increases with the strength of the magnetic field.
All of the above.
None of the above.
Answer: D) All of the above.
© 2014 Pearson Education, Inc.

20. Voting question
A current-carrying wire is oriented perpendicular to a magnetic field. The current in the wire is 2 A, the magnetic field has a strength of 5 T, and the length of the wire is 1 m. What is the force felt on the current-carrying wire due to the magnetic field?
0 N
2 N
5 N
10 N
Answer: D) 10 N
© 2014 Pearson Education, Inc.

21. Voting question
A current-carrying wire is oriented perpendicular to a magnetic field. The current in the wire is 2 A, the magnetic field has a strength of 5 T, and the length of the wire is 1 m. What is the force felt on the current-carrying wire due to the magnetic field?
0 N
2 N
5 N
10 N
Answer: D) 10 N
© 2014 Pearson Education, Inc.

22. Voting question
The torque that magnetic forces exert on a current-carrying coil:
Decreases with the number of loops in the coil.
Increases with the angle between the plane of the coil's surface and the direction of the magnetic field.
Decreases with the area of the loop.
Increases with the strength of the current.
Answer: D) Increases with the strength of the current.
© 2014 Pearson Education, Inc.

23. Voting question
The torque that magnetic forces exert on a current-carrying coil:
Decreases with the number of loops in the coil.
Increases with the angle between the plane of the coil's surface and the direction of the magnetic field.
Decreases with the area of the loop.
Increases with the strength of the current.
Answer: D) Increases with the strength of the current.
© 2014 Pearson Education, Inc.

24. Voting question
Which of the following statements is NOT correct about the magnetic dipole moment?
The direction of the dipole moment vector is perpendicular to the surface of the loop.
The bigger the dipole moment, the greater the torque that an external magnetic field exerts on it.
The magnetic dipole moment is the product of the current in an area of a loop.
All of the above are correct.
Answer: D) All of the above are correct.
© 2014 Pearson Education, Inc.

25. Voting question
Which of the following statements is NOT correct about the magnetic dipole moment?
The direction of the dipole moment vector is perpendicular to the surface of the loop.
The bigger the dipole moment, the greater the torque that an external magnetic field exerts on it.
The magnetic dipole moment is the product of the current in an area of a loop.
All of the above are correct.
Answer: D) All of the above are correct.
© 2014 Pearson Education, Inc.

26. Voting question
The magnetic force exerted by a magnetic field on an individual charged particle:
Increases with the speed of the particle.
Increases with the charge of the particle.
Increases with the strength of the magnetic field.
All of the above.
None of the above.
Answer: D) All of the above.
© 2014 Pearson Education, Inc.

27. Voting question
The magnetic force exerted by a magnetic field on an individual charged particle:
Increases with the speed of the particle.
Increases with the charge of the particle.
Increases with the strength of the magnetic field.
All of the above.
None of the above.
Answer: D) All of the above.
© 2014 Pearson Education, Inc.

28. Voting question
Using the right-hand rule for the magnetic force exerted by a magnetic field on a charged particle, we can determine that if the positively charged particle is moving into the page and the magnetic field is to the right, then the force is:
Into the page.
To the right.
Upward.
Downward.
Answer: D) Downward.
© 2014 Pearson Education, Inc.

29. Voting question
Using the right-hand rule for the magnetic force exerted by a magnetic field on a charged particle, we can determine that if the positively charged particle is moving into the page and the magnetic field is to the right, then the force is:
Into the page.
To the right.
Upward.
Downward.
Answer: D) Downward.
© 2014 Pearson Education, Inc.

30. Voting question
There is a positively charged particle at each of the points A, B, C, and D. Which particle will feel a force that is into the page? A B C D
Answer: A) A
© 2014 Pearson Education, Inc.

31. Voting question
There is a positively charged particle at each of the points A, B, C, and D. Which particle will feel a force that is into the page? A B C D
Answer: A) A
© 2014 Pearson Education, Inc.

32. Voting question
The particle at point A has a charge of +2.0 x 10−6 C and is moving at a speed of 3.0 x 107 m/s in the direction shown. What is the magnitude of the force from the magnetic field on the charged particle?
0 N
4.8 N
6 N
12 N
Answer: C) 6 N
© 2014 Pearson Education, Inc.

33. Voting question
The particle at point A has a charge of +2.0 x 10−6 C and is moving at a speed of 3.0 x 107 m/s in the direction shown. What is the magnitude of the force from the magnetic field on the charged particle?
0 N
4.8 N
6 N
12 N
Answer: C) 6 N
© 2014 Pearson Education, Inc.

34. Voting question
The magnetic field produced by a straight current-carrying wire:
Decreases as you move farther from the wire.
Decreases as the strength of the current decreases.
Both of the above.
None of the above.
Answer: C) Both of the above.
© 2014 Pearson Education, Inc.

35. Voting question
The magnetic field produced by a straight current-carrying wire:
Decreases as you move farther from the wire.
Decreases as the strength of the current decreases.
Both of the above.
None of the above.
Answer: C) Both of the above.
© 2014 Pearson Education, Inc.

36. Voting question
The magnetic field at the center of a loop with current I and a radius of 2 m is 4 T. What would be the magnetic field if the radius were changed to 1 m and the current stayed the same?
2 T
4 T
8 T
16 T
Answer: C) 8 T
© 2014 Pearson Education, Inc.

37. Voting question
The magnetic field at the center of a loop with current I and a radius of 2 m is 4 T. What would be the magnetic field if the radius were changed to 1 m and the current stayed the same?
2 T
4 T
8 T
16 T
Answer: C) 8 T
© 2014 Pearson Education, Inc.