Question

The poles of a horse-shoe magnet each of pole strength $2\text{Am}$ are at $4\text{cm}$ apart.

$\left(i\right)$The magnetic moment of the horse-shoe magnet is $\left(\text{in}{\text{Am}}^2\right)$

• A. $0.04$
• B. $0.06$
• C. $0.08$
• D. $0.02$

Answer 1

The correct option is C $0.08$

Given, $m=2\text{Am};2l=4\text{cm}=4\times {10}^{-2}\text{m}$

The magnetic moment is given by,

$M=m\left(2l\right)$

$M=2\times 4\times {10}^{-2}$

$=8\times {10}^{-2}{\text{Am}}^2\text{(or)}$

$M=0.08{\text{Am}}^2$

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