1. If moving charges are positive, then current flows in the direction of the charges. A.True B.False

2. If moving charges are negative, then current flows in the direction of the charges. A.True B.False

3. What direction must the current be flowing though the bar if it is accelerating to the right. A.Up B.Down

4. A conducting wire with positive moving charges has current as depicted. In what direction is the resulting magnetic force? A.to the left B.to the right C.towards the top of the screen D.towards the bottom of the screen E.into the screen F.out of the screen G.none of the above

5. A conducting wire with negative moving charges has current as depicted. In what direction is the resulting magnetic force? A.to the left B.to the right C.towards the top of the screen D.towards the bottom of the screen E.into the screen F.out of the screen G.none of the above

6. Magnetic field lines are induced by the current in a circular loop. In what direction will the magnetic field point at the very center of the loop? A.Towards the top of the loop B.Towards the bottom of the loop C.Towards the right of the loop D.Towards the left of the loop E.Out of the screen, normal to the loop. F.Into the screen, normal to the loop. G.Some strange off-center direction not listed above.

7. If the current carrying loop is replaced with two loops made of the same material, then the strength of the magnetic field in the center of the loops… A.stays the same B.is zero since the loops magnetic fields cancel. C.doubles in strength. D.halves in strength. E.(none of the above)

8. If the current carrying loop is replaced by a loop with twice the radius, the strength of the magnetic field at the center of the loop…. A.stays the same B.is four times the strength C.doubles in strength. D.halves in strength. E.is ¼ the strength. F.(none of the above)