A square loop ABCD , carrying a current `I,` is placed near and coplanar with a long straight conductor XY carrying a current I.

Options

A. there is no net force on the loop
B. the loop will be attracted by the conductor only if the current in the loop flows clockwise
C. the loop will be attracted by the conductor only if the current in the loop flows anticlockwise
D. the loop will always be attracted by the conductor

Answer

B

Explanation

Force on part BC and AD will be equal and opposite whether current is clockwise or anticlockwise.
Intensity of field is more at AB than at CD , therefore magnitude of force on AB will be more than CD . Therefore the loop will be attracted by the conductor if the current in the loop flows clockwise.