Jee Advanced
Magnetism
IIT-JEE 2012 Paper 1 Offline
INTEGER+4 / -02012
A cylinder cavity of diameter a exists inside a cylinder of diameter 2a as shown in the figure. Both the cylinder and the cavity are infinitely long. A uniform current density J flows along the length. If the magnitude of the magnetic field at the point P is given by \({N \over {12}}{\mu _0}aJ\), then the value of N is ______________.
