A magnet moves inside a coil. Consider the following factors: Which can affect the emf induced in the coil?
A) I only
B) II only
C) III only
D) I and II only
E) I, II, III

Question

A magnet moves inside a coil. Consider the following factors:  Which can affect the emf induced in the coil?
A) I only 
B) II only 
C) III only 
D) I and II only 
E) I, II, III

Quizplus · Accepted Answer

I) Velocity of the magnet relative to the coil affects the induced emf because a changing magnetic field induces an emf in the coil according to Faraday's law. The faster the magnet moves, the faster the magnetic field changes and the greater the induced emf.
II) Strength of the magnetic field affects the induced emf because the magnetic field determines the rate of change of the magnetic flux through the coil, which is another way of describing the changing magnetic field that induces the emf. A stronger magnetic field can induce a larger emf.
III) Orientation of the coil relative to the magnetic field doesn't affect the induced emf because the emf is only related to the rate of change of the magnetic field, not the orientation of the coil.

A Magnet Moves Inside a Coil