A current of 4.0 A is maintained in a single circular loop having a circumference of 80 cm.An external magnetic field of 2.0 T is directed so that the angle between the field and the plane of the loop is 20$\degree$.Determine the magnitude of the torque exerted on the loop by the magnetic forces acting upon it.
A)0.41 N.m
B)0.14 N .m
C)0.38 N . m
D)0.27 N .m
E)0.77 N .m

Question

Quizplus · Accepted Answer

The torque on a current-carrying loop in a magnetic field is given by the equation τ = NIABsinθ, where N is the number of turns in the loop, I is the current, A is the area of the loop, B is the magnetic field strength, and θ is the angle between the magnetic field and the plane of the loop. In this case, N = 1, I = 4.0 A, A = πr^2 = π(0.4 m)^2 = 0.16π m^2, B = 2.0 T, and θ = 20°. Therefore, τ = (1)(4.0 A)(0.16π m^2)(2.0 T)sin(20°) = 0.38 N·m. The best choice is C.

A Current of 4 °\degree° Determine the Magnitude of the Torque Exerted on the Loop

A Current of 4 $\degree$ Determine the Magnitude of the Torque Exerted on the Loop