A square loop of wire with a small resistance is moved with constant speed from

Question

A square loop of wire with a small resistance is moved with constant speed from a field free region into a region of uniform B field (B is constant in time) and then back into a field free region to the right. The self inductance of the loop is negligible. When leaving the field the coil experiences a magnetic force to the left. Upon entering the field, a clockwise current flows in the loop. Upon leaving the field, a clockwise current flows in the loop. When entering the field the coil experiences a magnetic force to the right.

Explanation / Answer

a)
When leaving the field, B is decreasing so induced current will be such that its magnetic field is coming out of plane
So induced current is couter clockwise
Force on the left wire towards left and hence net force will be towards left
Force on upper wire of loop balances force on lower wire
Force on right wire = 0 as it is outside magnetic field area

Answer: True

b)
when enetreing the field, B is increasing , so induced current will be such that its magnetic field is directed into the plane
So, induced current will be clockwise
Answer: True

c)
As explained in part a , current will be counterclockwise
Answer: False

d)
When entering current is clockwise
force on right loop will be towards left
Force on upper wire of loop balances force on lower wire
Force on left wire = 0 as it is outside magnetic field area
so net magnetic field will be towards left
Answer: False

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