Question

A solenoid of length $0.4$ m and having $500$ turns of wire carries a current $3$ A. A thin coil having $10$ turns of wire and radius $0.1$ m carries a current $0.4$ A. The torque produced to hold the coil in middle of solenoid with its axis perpendicular to the axis of the solenoid is $(\mu_0=4\pi\times10^{-7}$ SI units, $\pi^2=10$, $\sin90^\circ=1)$

• A. $3\times10^{-6}\ \text{Nm}$
• B. $12\times10^{-6}\ \text{Nm}$
• C. $6\times10^{-4}\ \text{Nm}$
• D. $24\times10^{-6}\ \text{Nm}$

Hint:

Physics Tip : Torque on coil in magnetic field: $\tau=N I A B \sin\theta$.

Answer 1

The Correct Option is C