Question

The diagram shows a solenoid carrying time varying current $I=I_{0}t$. On the axis of this solenoid a ring has been placed. The mutual inductance of the ring and the solenoid is $M$ and the self inductance of the ring is $L$. If the resistance of the ring is $R$, then the maximum current which can flow through the ring is equal to

• A. $\frac{(2M+L)I_0}{R}$
• B. $\frac{M{I}_0}{R}$
• C. $\frac{(2M-L)I_0}{R}$
• D. $\frac{(M+L)I_0}{R}$

Answer 1

The correct option is B $\frac{M{I}_0}{R}$

We know that,
Induced emf in ring $=M\frac{dI}{dt}=M{I}_0$
max. current in ring $=\frac{M{I}_0}{R}$
as in LR circuit with constant emf source, the effective resistance is equal to the value of resistance of the resistor present.