Question

A bar magnet of length 0.1 m and with a magnetic moment of `5Am^(2)` is placed in a uniform a magnetic field of intensity 0.4T, with its axis making an angle of `60^(@)` with the field. What is the torque on the magnet ?

Answer 1

Given, `2l = 0.1 m, m = 5A - m^(2), B = 0.4T, theta = 60^(@)`.
Torque, `T = mB sin theta = 5 xx 0.4 xx sin 60^(@) = 2 xx (sqrt(3))/(2)`
`:. T = 1.732 N - m`