Two circular coils P & Q are coaxially & carry currents `I_1` and `I_2` respectively (all direction are w.r.t. the observer)

Options

A. If `I_(2)=0` and P moves towards Q, a current in the same direction as `I_(1)` is induced in Q
B. If `I_(1)=0` and Q moves towards P,a current in the oppsite direction to that `I_(2)` is induced in P,
C. when `I_(1) ne 0` and `I_(2) ne0` are in the same direction then the two coils tend to move apart.
D. when `I_(1) ne 0` and `I_(2)ne 0` are in opposite directions then the coils attract each other

Answer

B

Explanation

When Q is brought towards P, north and south poles will be induced at P as shown in the figure. Which is as a result of current in P in opposite direction as that of Q