Figure shows cross section of two large parallel metal sheets carrying electric currents along their surface. The current in each sheet is `10//pi A//m` along the width, Consider two points A and B, as shown in the figure with their positions.

Options

A. Magnetic field at A is `4muT` along positive X-direction
B. Magnetic field at A is `4muT` along negative X-direction
C. Magnetic field at B is zero
D. Magnetic field at B is `2muT` along X-direction.

Answer

A, C

Explanation

Field due to each plate `=1/2mu_(0)K=2muT`
At A, fields add up being in the same directions whereas at B, cancel out due to opposite direction.