Question

What is electrostatic shielding? Mention one application of it.

Answer 1

Hint: Shielding means covering to protect from something. In electrostatics, the electric field inside the conductor is zero. To protect a sensitive element or instrument from an external electric field we put a covering of conductor, so that electric field inside it becomes zero and our sensitive instrument remains safe.

Complete step-by-step answer:
Let us know what is electrostatic shielding.
It is the phenomena of protecting a certain region of space from external fields,we know that electric field inside a conductor is zero therefore to protect delicate instruments from external electric fields we enclose them in hollow conductors, such hollow conductors are called Faraday cages they need not to be earth.
And in a thunderstorm accompanied by lightning it is safer to be inside a car or a bus then to be in open ground or under a tree. The metallic body of the car or bus provides electrostatic shielding from the lightning.
This fundamental fact is that electric field inside a cavity is zero whatever with the size and shape of the cavity and whatever be the charge on the conductor and the external fields in which it might be placed that is whatever be the charge an electric field configuration outside cavity in a conductor remains protected from outside electrical influence.
The question arises why the electric field inside the conductor is zero. This is the property of the conductor that if you put a charge on the surface of the conductor the charge will automatically spread all over the body of the conductor in equal proportions. The electric field produced by each charge is perpendicular to the surface area of the conductor hence each charge will nullify the effect of other charges which in result gives the electric field zero inside the conductor.
This phenomena helps in electrostatic shielding.
Application of electrostatic shielding:
It has been used in protecting sensitive instruments from outside electrical influence.
This phenomenon has also been used in the design of TV cables.

Note: Like the phenomena of electrostatic shielding there is a phenomena of magnetic shielding which suggest that the magnetic field inside the cavity is zero this will help us to design sensitive and costly watches and place them inside the cavity, so that there is no effect of external magnetic field.