1. The unit of the magnetic field B (the Tesla) A] is the same as the electric field times a velocity B] is the same as the electric field divided by a velocity C] cannot be expressed as either of these (The electric field is V/m.)

2. What is the sign of the charge carriers in this conductor? A] + B] - C] Can’t tell

3. What is the drift velocity of the negative charge carriers? A] 0 B] 10 -3 m/s C] 10 -2 m/s D] 10 -1 m/s E] 1 m/s

4. A proton (+) and an electron (-) move side by side both with velocity v as shown. What is the direction of the magnetic field at the electron due to the proton (in our “laboratory” frame of reference)? A] into page B] out of page C] upward D] downward E] to the right

5. A proton (+) and an electron (-) move side by side both with velocity v as shown. The magnetic field is into the page, by RHR. What is the direction of the magnetic force on the e- ? A] into page B] out of page C] upward D] to the left E] to the right

6. A proton (+) and an electron (-) move side by side both with velocity v as shown. The magnetic force on the electron is away from the proton. What direction is the total (electric + magnetic) force on the electron? (v<c) A] into page B] out of page C] upward D] to the left E] to the right

7. A proton (+) and an electron (-) move side by side both with velocity v as shown. The total force on the electron is still attractive, but weaker than if no magnetic force were present. What is the total force on the electron if v=c? A] 0 B] infinite, away from the proton C] infinite, toward the proton

8. A proton (+) and an electron (-) move side by side both with velocity v as shown. The total force on the electron is still attractive, but weaker than if no magnetic force were present. What is the total force on the electron if v=c? Ans 0! Clocks slow to a STOP as v -> c!

9. What is the contribution of the straight sections of the wire to the magnetic field in the center of the semicircle? A] Each contributes 0 B] They both have contributions that are opposite, and so add to 0 C] Each contributes D] infinite

10. Point P is a perpendicular distance x from each wire. Both wires carry current I in the direction shown. What is the magnetic field at P? A] 0 B] C] D] Insufficient information