Question

A circular coil of 216 turns has a radius of 2.32 cm. (a) Calculate the current that results in a magnetic dipole moment of magnitude 2.89 A·m2. (b) Find the maximum magnitude of the torque that the coil, carrying this current, can experience in a uniform 46.0 mT magnetic field.

Answer 1

(a) 7.92 A

(b) 0.133 Nm

Step-by-step explanation:

N = 216

r = 2.32 cm = 0.0232 m

(a) M = 2.89 Am^2

M = N i A

Where, A be the area of the coil and i be the current in the coil

2.89 = 216 x i x 3.14 x 0.0232 x 0.0232

i = 7.92 A

(b) B = 46 mT = 0.046 T

Torque, τ = M B Sin 90

τ = 2.89 x 0.046 x 1 = 0.133 Nm