Question

Figure shows a square current carrying loop ABCD of side 2m and current $I=\frac{1}{2}A$. The magnetic moment $\overrightarrow{M}$ of the loop is:

• A. $(\hat{i}-\sqrt{3}\hat{k})A-m^2$
• B. $(\hat{j}-\hat{k})A-m^2$
• C. $(\sqrt{3}\hat{i}-\hat{k})A-m^2$
• D. $(\hat{i}-\hat{k})A-m^2$

Answer 1

The correct option is A $(\hat{i}-\sqrt{3}\hat{k})A-m^2$

$\overline{M}=I(-2cos30\hat{i}-2sin30\hat{k})\times \left(2\hat{j}\right)=I(\hat{i}-\sqrt{3}k)2$