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A long cylindrical kept along Z-axis carries a current density $${\bf{\hat J}} = {J_0}r{\bf{\hat k}},$$   where $${J_0}$$ is a constant and r is the radial distance from the axis of the cylinder. The magnetic induction $$\overrightarrow {\bf{B}} $$ inside the conductor at a distance d from the axis of the cylinder is

A long cylindrical kept along Z-axis carries a current density $${\bf{\hat J}} = {J_0}r{\bf{\hat k}},$$   where $${J_0}$$ is a constant and r is the radial distance from the axis of the cylinder. The magnetic induction $$\overrightarrow {\bf{B}} $$ inside the conductor at a distance d from the axis of the cylinder is Correct Answer $$\frac{{{\mu _0}{J_0}{d^2}}}{3}\hat \phi $$

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