A rectangular coil lies flat on a horizontal surface. A bar magnet is held above the center of the coil with its north pole pointing down. If the magnet is dropped from this position what is the direction of the induced current in the coil?
A) There is no current in the coil.
B) counterclockwise
C) clockwise
D) Not enough information is provided.

Question

Quizplus · Accepted Answer

The changing magnetic field due to the falling magnet induces an emf in the coil, which in turn drives a current. The direction of the induced current is such that it opposes the change in magnetic flux. In this case, the magnetic flux through the coil is increasing, so the induced current will be in a direction that creates a magnetic field that opposes the increasing flux. This means that the induced current will be counterclockwise.

A Rectangular Coil Lies Flat on a Horizontal Surface