16. Which of the following is not a property of magnetic field lines?
a) They never intersect
b) They always form closed loops
c) They are closer together in stronger magnetic fields
d) They are farther apart in stronger magnetic fields
17. In which direction do the magnetic field lines inside a current-carrying wire point?
a) Towards the wire
b) Away from the wire
c) In a clockwise direction
d) In a counterclockwise direction
18. The strength of the magnetic field around a current-carrying wire:
a) Increases with increasing current
b) Decreases with increasing current
c) Remains constant regardless of the current
d) Depends on the resistance of the wire
19. Which of the following is not a unit of magnetic field strength?
a) Gauss
b) Tesla
c) Ampere
d) Weber
20. The magnetic field inside a solenoid is:
a) Zero
b) Strongest at the center
c) Strongest at the ends
d) Weakest at the center
