Question

A current of 16.0 mA is maintained in a single circular loop of 1.90 m circumference. A magnetic field of 0.790 T is directed parallel to the plane of the loop.(a) Calculate the magnetic moment of the loop.mA · m2(b) What is the magnitude of the torque exerted by the magnetic field on the loop?mN · m

Answer 1

given,

current (I) = 16 mA

circumference of the circular loop (S)= 1.90 m

Magnetic field (B)= 0.790 T

S = 2 π r

1.9 = 2 π r

r = 0.3024 m

a) magnetic moment of loop

M= I A

M=
`16 * 10^(-3) * \pi * r^2`

M=
`16 * 10^(-3) * \pi * 0.3024^2`

M=
`4.59 * 10^(-3)\ A m^2`

b) torque exerted in the loop

`\tau = M\ B`

`\tau = 4.59 * 10^(-3)* 0.79`

`\tau = 3.63 * 10^(-3) N.m`