30.12
If a stationary conductor is placed in a changing magnetic field, an induced current starts flowing in the conductor.
The source of this induced current is an electric field that is produced due to a change in magnetic flux. This field is called the induced electric field.
Consider a solenoid having 'n' number of turns per unit length. Current 'I' is passed in the solenoid, which produces a magnetic field 'B'.
A conducting loop attached to a galvanometer is placed around the solenoid.
If the current in solenoid winding increases, the magnetic flux will also increase, and an induced current is produced in the conducting loop due to the induced electric field 'E'.
According to Faraday’s law, an electromotive force is also produced in the conducting loop.
Also, the work done by the induced electric field is the line integral around a closed path and is equal to the induced electromotive force.
Thus, Faraday's law can be restated in terms of the induced electric field.
The fact that emfs are induced in circuits implies that work is being done on the conduction electrons in the wires. What can possibly be the source o…
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