The relation between `mu_r andX_m` is `mu_r=1+X_m` How will you arrive at this relation ? Explain.

Explanation

We have total magnetic induction `B=B_0+B_m`
where `B_0` - magnetic induction in free space.
`B_0=mu_0H,B_m=mu_0I and B=muH " ":. muH=mu_0H+mu_0I`
But `mu =mu_rmu_0 " ":.mu_rmu_0H=mu_0H+mu_0I`
`mu_rH=H+I=(H+I)/H=1+I/H=1+X_m:.mu_r=1+X_m`