Magnetism and Matter question for NEET / JEE Main, with solution

Answer: (A) $0.5\pi\ \text{A m}^2$

Concept. A current loop of $N$ turns has magnetic moment $M = NIA$.

Step 1. Area. $A = \pi(0.05)^2 = 2.5\pi \times 10^{-3}\ \text{m}^2$.

Step 2. Moment.
$$M = 100 \times 2 \times 2.5\pi \times 10^{-3} = 0.5\pi\ \text{A m}^2$$

Answer. $0.5\pi\ \text{A m}^2$ (Option A).

Solution by Sreeraj P, M.Sc Physics