Question

A straight wire of length 0.5 metre and carrying a current of 1.2 ampere is placed in a uniform magnetic field of induction 2 Tesla . The magnetic field is perpendicular to the length of the wire . The force on the wire is (1) 2.4N (2) 1.2 N (3) 3.0N (4) 2.0N

Answer 1

The Ampere’s force law states
F=BIl sin⁡α
So
F=2×1.2×0.5×sin⁡〖90°=1.2 N〗