Question

PHY
1. The current in a coil of inductance
0.2 H changes from 5 A to 2 A in
0.5 sec. The magnitude of the average
induced emf in the coil is
(A) 12V (B) 30 V
(C) 0.3 V (D) 0.6V
​

Answer 1

Answer:

Answer:

Magnitude of the Average induced EMF in the coil is 1.2V.

Given:

Self inductance,L=0.2H

change in time,t=0.5seconds

change in current,di=2-5=-3A

solution:

As we know,

From the Faraday second law,

The induced EMF in the coil is equal to the negative rate of change of magnetic flux in the coil.

e=-d∅/dt

And,induced EMF in the circuit

e=-L×di/dt

The magnitude of the average induced EMF in the coil,

|d∅/dt|=-L×di/dt

|d∅/dt|=0.2×30/5

|d∅/dt|=1.2V

Explanation:

Hope it helps you frnd.......