Question

What is the total force on any arbitrary current carrying loop in a uniform magnetic field ? Prove your answer

Answer 1

The force is zero.

Explanation:

The force on a current carrying wire moving in a uniform magnetic field `B` is given by:

`F=I (BxxL)`

The direction of the vector `L` is the same as the direction of the current through the wire `(I)`.

If the wire is a closed loop then vector `L` starts and finishes at the same place so is zero.

So:

`F=I(Bxx0)=0`