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5.
The bar magnet is removed, and the loop is placed in a region with a uniform constant magnetic field, as shown
above. The loop then undergoes simple harmonic motion, moving up and down vertically. Which of the following
statements correctly describes the resulting induced current, if any?
(A) The induced current is nonzero and constant.
(B) The induced current oscillates at the same frequency as the loop.
(C) The induced current oscillates at twice the frequency as the loop.
(D) The induced current is zero.
Is there a force exerted by the magnet on the loop as the magnet falls through it? Why or why not?
(A) No. Because the loop is not magnetized, it will not be affected by the magnet.
(B) No. Because the loop is not moving, there are no forces on it.
(C) Yes. Because the magnetic field due to current in the loop exerts a force on the magnet, the magnet also
exerts a force on the loop.
(D) Yes. Because gravity acts on the loop, the magnet must exert a force on the loop to keep it at rest.
