Question

prove this
thanks in advance

Answer 1

can you make the Hindi sentence of this question

Answer 2

let, a magnet NS of length r be kept at an angle ß with the uniform electric field
B. current through it be I & A be area of current loop
the forces of magnitude F effect on N& S poles r equal but opposite in direction, so, they constitute a couple.
the perpendicular distance between the two forces =rsinß
torque acting on the magnet = Frsinß
also magneting dipole is Pm=IA
then torque = IA×B=Pm ×B
or, torque=PmBsinß
this torque is stored as potential energy inside the magnet bar & its direction is negetive. hence U=-Pm×B