A straight wire of mass 200 g and length 1.5 m carries a current of 2 A. It is suspended in mid-air by a uniform horizontal magnetic field B. What is the magnitude of the magnetic field ?

0.65 T 1.55 T 0.45 T 2 T

0.65 T

mg = ILB B = mg/IL m = 200 g ; g = 9.8 m/s2 ; I = 2 A ; L = 1.5 m B = 0.65 T