A bar magnet of magnetic moment `1.5 JT^(-1)` lies aligned with the direction of a uniform magnetic field of 0.22 T .
a . What is the amount of work required by an external torque to turn the magnet so as to align its magnetic moment : (i) normal to the direction , (ii) opposite to the field direction ?
b. What is the torque on the magnet in cases (i) and (ii) ?

Explanation

`m = 1.5 "JT"^(-1), B = 0.22T`
a. i mB = 0.330 J `" "ii.2mB=0.66J`
b. i. Maximum = 0.33 , tending to turn it towards the direction of the field.
ii. Zero `(sin 180^@=0)`