There are two coils `A` and `B` as shown in Figure. A current starts flowing in `B` as shown, when `A` is moved towards `B` and stops when `A` stops moving. The current in `A` is counterclockwise. `B` is kept stationary when `A` moves. We can infer that

Options

A. there is a constant current in clockwise direction in A
B. there is a varying current in A
C. there is no current in A
D. there is a cinstant current in the counter-clockwise direction in A

Answer

D

Explanation

When A stops moving the current in B become zero, possible only if the current in A is constant. If the current in A would be variable, then there must be an induced emf (current) in B even, if A stops moving.