Question

A tangent galvanometer has a coil of 2 turn of mean radius 7.5cm, which is set with its plane in the magnetic meridian. A current is passed through the coil and produces a deflection of a magnet, pivoted at the center of the coil, of 450. Calculate the current if the horizontal component of the earth’s flux density is 1.8×10^−5Wbm^−2

a. 1.07A
b. 3.27A
c. 1.33A
d. 2.15A