Question

A 200 turn circular loop of radians 45 cm is vertical, with its acts on a line running east to west. A current of 95A circulates clockwise in the loop when viewed from the east. The Earth fields here is due north, parallel to the Ground, with a strength of 3.25 times 10^-5 T. What is the magnitude of the torque on the loop in N.m?

Answer 1

The magnitude of torque on the loop will be:

$\tau = \mu Bsin\theta$

=> $\tau = N [\pi r^2 I] Bsin90\degree$

N = 200

so, $\tau = 200 [\pi (0.45)^2 95] (3.25\times 10^{-5})sin90\degree = 0.3928 Nm$ .