a wire of length 20 cm and mass 50 mg flies in air or floats . it lies in direction 30 degree east of north , magnetic field of earth at this site is 8*10^-3 . what current must be passed through the wire in about horizontal field Share with your friends Share 1 Sanjay Singh answered this Dear student Magnetic field of the earth is directed from north to south .Angle between the current and the horizontal component of the earth magnetic field is 30°.Magnetic force on the wire is F→=i(l→×B→)F=Bilsinθ (This force is directed in the upwards direction as is quite evident from the cross product of the current and the magnetic field )Now from the free body diagram of the wire .For equilibriummg=Bilsinθi=mgBlsinθ=50×10-3×108×10-3×0.2×12=50×10-3×10×28×10-3×0.2=50×10×28×0.2=10001.6=625 ARegards 6 View Full Answer
