A coil is wrapped with 140 turns of wire on the perimeter of a square frame of sides 35 cm. Each turn has the same area, equal to that of the frame, and the total resistance of the coil is 1.46 . A uniform magnetic field is turned on perpendicular to the plane of the coil. If the field changes linearly from 0 to −0.426 Wb/m2 in a time of 1.19 s, find the magnitude of the induced emf in the coil while the field is changing. Answer in units of V.

The magnitude of the induced emf in the coil is 6.13 V.

Explanation:

Given that,

Number of turns in a coil, N = 140

Side of a square frame, s = 35 cm = 0.35 m

A uniform magnetic field is turned on perpendicular to the plane of the coil. The the field changes linearly from 0 to in a time of 1.19 s.

We need to find the magnitude of the induced emf in the coil while the field is changing. Due to change in field, an emf is induced in it. It is given by :

A is area of square frame,

So, the magnitude of the induced emf in the coil is 6.13 V.

need to see circuit to get time constant

it doesn't. it was imagined up in the middle ages.