Question

Two magnets, each of magnetic moment $M$ are placed so as to form a cross at right angles to each other. The magnetic moment of the system will be

• A. $2M$
• B. $\sqrt{2}M$
• C. $0.5M$
• D. $M$

Answer 1

The correct option is B $\sqrt{2}M$



The resultant magnetic moment of the system is,

$M_{net}=\sqrt{M_1^2+M_2^2+2M_1{M}_2\cos \theta }$

$\because M_1=M_2=M\text{and}\theta ={90}^{\circ }$

$\therefore M_{net}=\sqrt{2M}$

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Hence, $\left(B\right)$ is the correct answer.