Question

An iron rod is placed parallel to magnetic field of intensity $2000A/m$. The magnetic flux through the rod is $6\times 10^{-4}Wb$ and its cross-sectional area is $3c{m}^2$. The magnetic permeability of the rod in $wb/A-m$ is

• A. $10^{-1}$
• B. $10^{-2}$
• C. $10^{-3}$
• D. $10^{-4}$

Answer 1

Answer: (C)

Cross-sectional area $A=3\times 10^{-4}{m}^2$
Magnetic flux through the rod $\varphi =6\times 10^{-4}Wb$
Magnetic field intensity $H=2000A/m$
Using $\varphi =BA$ and $B=\mu H$
We get magnetic permeability $\mu =\frac{\varphi }{AH}$
$\therefore \mu =\frac{6000}{3\times 10^{-4}\times 2000}=10^{-3}\frac{Wb}{A-m}$