Question

An infinitely long cylinder of radius $R$ carries a frozen-in magnetization $\vec{M} = ke^{-s}\hat{z}$, where $k$ is a constant and $s$ is the distance from the axis of the cylinder. The magnetic permeability of free space is $\mu_0$. There is no free current present anywhere. The magnetic flux density ($\vec{B}$) inside the cylinder is

• A. 0
• B. $\mu_0 ke^{-R} \hat{z}$
• C. $\mu_0 ke^{-s} \hat{z}$
• D. $\mu_0 ke^{-s} \left( \frac{R}{s} \right) \hat{z}$

Answer 1

Answer: (C)

$\mu_0 ke^{-s} \hat{z}$

Answer 2

The correct option is (C) :$\mu_0 ke^{-s} \hat{z}$