Question

The mass of an iron rod is $80$ $gm$ and its magnetic moment is $10$ $A{m}^2$. If the density iron is $8$ $gm/cc$, then the value of intensity of magnetization will be

• A. ${10}^6$ $A/m$
• B. ${10}^4$ $A/m$
• C. ${10}^2$ $A/m$
• D. $10$ $A/m$

Answer 1

The correct option is A ${10}^6$ $A/m$

$B=\frac{M}{V}$

$M=10$ $A{m}^2$

$Density=8$ $gm/cc$

$\frac{mass}{V}=8\times {10}^6$ $gm/m^3$

$\Rightarrow V=\frac{80}{8\times {10}^6}$

$\Rightarrow V={10}^{-5}$ $m^3$

So, $B=\frac{10}{{10}^{-5}}$ $A/m$

$\Rightarrow B={10}^6$ $A/m$