A square current carrying loop is suspended in a uniform magnetic field acting in the plane of the loop. If the force on one arm of the loop is `vec(F)`, the net force on the remaining three arms of the loop is

Options

A. `-3 vec F`
B. `vec F`
C. `3 vec F`
D. `- vec F`

Answer

D

Explanation

Net force on current loop, placed in uniform magnetic field is zero, hence forces on all four wires must add to zero
Therefore, the net force on the three wires is: `- vec F`