A circular coil of 20 turns and radius 5 cms is placed with its plane oriented at 90° to a magnetic field of 0.1 T.The field is now increased at a steady rate,reaching a value of 0.5 T after 4 seconds.What emf is induced in the coil?
A)0.016 V
B)0.021 V
C)0.026 V
D)0.031 V
E)0.036 V

Question

Quizplus · Accepted Answer

The emf induced in the coil is given by the equation:emf = -N * (dΦ/dt)where:N is the number of turns in the coilΦ is the magnetic flux through the coildt is the time interval over which the flux changesIn this case, the magnetic field is increasing at a steady rate, so the flux through the coil is also increasing at a steady rate. The rate of change of the flux is:dΦ/dt = B * A / twhere:B is the magnetic field strengthA is the area of the coilt is the time intervalSubstituting these values into the equation for emf, we get:emf = -N * B * A / tPlugging in the given values, we get:emf = -20 * 0.1 T * π * (0.05 m)^2 / 4 s= -0.016 VTherefore, the correct answer is A) 0.016 V.

A Circular Coil of 20 Turns and Radius 5 Cms