'Inside a conductor,the electrostatic field is zero'. Explain.

(N/A) In the static situation,when there is no current inside or on the surface of the conductor,the electric field is zero everywhere inside the conductor.
$A$ conductor contains free electrons. If there were an electric field inside,these free charge carriers would experience a force $(F = qE)$ and would drift,creating a current.
In the static situation,the free charges redistribute themselves on the surface of the conductor such that the internal electric field produced by these charges exactly cancels the external applied electric field. Consequently,the net electric field becomes zero everywhere inside the conductor.