Question

A circular coil of $20$ turns and radius $10 \,cm$ is placed in uniform magnetic field of $0.10\,T$ normal to the plane of the coil. If the current in coil is $5 \,A$, then the torque acting on the coil will be

• A. $31.4\,Nm$
• B. $3.14\,Nm$
• C. $0.314\,Nm$
• D. zero

Answer 1

Answer: (D)

zero

Answer 2

Since $\theta=0^{\circ}$ so tau $=0(\because \tau= NiAB \sin \theta)$