A circular 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,as viewed from above?
A)counterclockwise
B)clockwise
C)An emf but no current is induced in the coil.
D)There is no current in the coil.

Question

Quizplus · Accepted Answer

According to Lenz's Law, the direction of the induced current in the coil will be such that it opposes the change that caused it. As the north pole of the magnet approaches the coil, the coil will generate a magnetic field to oppose the increase in magnetic flux. This means the coil will act like a magnet with its north pole facing up, to repel the approaching north pole of the bar magnet. Viewed from above, this requires a counterclockwise current in the coil.

A Circular Coil Lies Flat on a Horizontal Surface