Q. A circular coil having $N$ turns is made from a wire of length $L$ meter. If a current $I$ ampere is passed through it and is placed in a magnetic field of $B$ $tesla$, the maximum torque on it is
A) Directly proportional to $N$
B) Inversely proportional to $N$
C) Inversely proportional to $N^{2}$
D) Independent of $N$
Explanation
(a) Because $\tau_{\max} = BiNA\ \Rightarrow \tau \propto B$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.