When you drop the north pole of a permanent magnet onto an aluminum sheet, it falls slightly slower than normal. The magnet is being repelled by the aluminum because
A) aluminum is positively charged and repels approaching magnetic poles.
B) aluminum has a net north magnetic pole that repels any approaching north poles.
C) aluminum has a net south magnetic pole that repels any approaching north poles.
D) current induced in the aluminum by the approaching north pole produces a repelling north pole on the aluminum's surface.

Question

Quizplus · Accepted Answer

When a magnet moves towards a conductor like aluminum, it induces electric currents (known as eddy currents) in the conductor. According to Lenz's law, these currents create their own magnetic field which opposes the change that caused them. In this case, the induced magnetic field in the aluminum acts to repel the approaching north pole of the magnet, slowing its fall. This is a manifestation of electromagnetic induction, not a result of permanent magnetic properties or static electric charges in the aluminum.

When You Drop the North Pole of a Permanent Magnet