Explain electrostatics of conductors. Explain the effects produced inside a metallic conductor placed in an external electric field.

Explanation

In metallic conductors the charge carriers are electrons. In a metal the outer (valance) electrons part away from their atoms and are free to move. These electrons are free from parent atom but not free to leave the metal. Hence, free electrons form a kind of .gas.. Free electron collide with each other and with the ions and move randomly in different directions.
In an external electric field they drift against the direction of the field and get deposited on the surface and an equal amount of positive charge can be considered as deposited on the surface ( other end). This is shown in below figure.

The induced charges produce an electric field inside the conductor in the direction opposite to the external electric field.
When the external electric field and internal electric field become equal in magnitude the charges stop to deposit on the surface.