Question

Choose the incorrect statement. Induced electric field
A. Is produced by varying magnetic field
B. Is non conservative in nature
C. Cannot exist in a region not occupied by magnetic field
D. None of the above

Answer 1

Hint: We know that a non-conservative field is induced in the circuit, when the magnetic flux through a circuit changes. This field is called an induced electric field. This induced field will give rise to the current in the circuit.

Complete step by step answer:
Here, we will discuss each step one by one as given below:
A. Now, according to Faraday's experiment, the varying magnetic field can produce induced electric fields. Therefore, the first statement is correct.

B. Now, consider a superconducting ring. The area of cross-section of the ring will be parallel to the magnetic field and the magnetic field inside a ring a will be increasing. The electrons in the ring will be accelerated due to the induced electric field. Also, after travelling the distance of circumference of the rings, the electrons will acquire some energy. Therefore, after travelling in a closed loop, the work done by the electric field on the electrons will be zero. This means that the electric field is non-conservative. Hence, the second statement is incorrect.

C. Now, consider a bigger concentric ring. When the magnetic field inside the ring will increase, the electric flux associated with the ring will change. Even when the magnetic field does not exist outside the ring, there will be an electric field outside the ring. Hence, this statement is incorrect.

Therefore, option C is the correct.

Note:The induced electric field is non-conservative in nature because a net work is done by this field in moving a charge over a closed path. Also, the induced electric field can exist even if there is no magnetic field. This is because the magnetic field is caused by the electric field obtained by moving charges.