Question

The net electric field inside an insulator kept in a uniform electric field get

• A. Increases
• B. Decreases
• C. Zero
• D. Increases near entery and decreases near exit

Answer 1

The correct option is B Decreases

For any insulator kept in the uniform electric field, the electric field lines configuration will be as shown in the figure.


The electric field lines entering the insulator, induces localized negative charge at the entry surface and localized positive charge at the exit surface. Unlike the conductor, there is no movement of free electrons to the left. Thus, the induced electric field is of low magnitude which does not cancel the external field.

$E_{net}=E_0-E_{ind}\ne 0$

Therefore, the net electric field inside an insulator kept in the uniform electric field get decreases.