Question

The magnetic moment of a bar magnet is $3.6\times {10}^{-3}A-m^2$. Its pole strength is $120mA-m$. Its magnetic length is :

• A. $3cm$
• B. $0.3cm$
• C. $33.33cm$
• D. $3\times {10}^{-2}cm$

Answer 1

Answer: (A)

$3cm$

$\text{Magnetic length = Magnetic Moment/Pole Strength}$

$=\frac{3.6\times {10}^{-3}}{(120\times {10}^{-3})}=0.03m=3cm$