Average power loss in a rotating coil in 1 rotation is Pavg=
emax.Imax
2
=
emax2
2R
=
(NBAω)2
2R
......(i) Here, number of turns, N=40 Intensity of magnetic field, B=0.05T Area of coil, A=0.01m2 Angular speed, ω=50rad∕s Resistance of closed loop of coil, Average power loss, Pavg=25mW =25×10−3W So, fromeq. (i) we have 25×10−3=