Question

A conductive loop is withdrawn from a region with a uniform magnetic field. Upon leaving the field, the loop undergoes an emf that produces an induced current. What interaction will we have between the coil and the magnetic field?


a)Attraction
b)There is no net force but there will be a torque on the turn.
c)There is no force or torque on the coil.
d)Repulsion.

Answer 1

If the conducting loop is moving out of the magnetic field, then the magnetic flux through that loop decreases. The change in magnetic flux produces induced emf which in turn proudces induced current which is responsible for induced magnetic field.

The main purpose of induced emf and induced magnetic field is to oppose the change in magnetic flux. The magnetic flux is decreasing only because the loop is moving out of the magnetic field. Then the induced magnetic field should oppose the motion in order to oppose the decrease in flux. This is possible if the existing magnetic field ATTRACTS the loop so that the coil motion is retarded.

The interacation between the magnetic field and the conducting loop is Attraction.

OPTION A