A copper is placed in the center of an air gap between two magnetic poles, as shown in the figure.

Question

A copper is placed in the center of an air gap between two magnetic poles, as shown in the figure. The field is confined to the gap and has a strength of 1.6 T.

a. Determine the force on the wire when the switch is open.

b. Determine the force on the wire when the switch is closed.

Answer 1

The force of a magnetic field on a wire is ILB for a wire perpendicular to a field. I is the current, L is length of the wire experiencing the field, and B is the magnetic field. There is no force in a. In b, you have to know the current and the length of wire in the field.