Explain electrostatic shielding with necessary diagram.
Explain electrostatic shielding with necessary diagram.
Consider a conductor with a cavity as shown in figure.
There is no charges inside the cavity.
Whatever be the size and shape of the cavity.
If a conductor with cavity placed in external electric field, its electric field in cavity remain zero.
If the conductor is charged or charges are induced on a neutral conductor by an external field, all charges reside only on the outer surface of a conductor with cavity.
Any cavity in a conductor remains shielded from outside electric influence. This is known as electrostatic shielding.
When we are in the car and there is thunder with lighting in the sky, we should closed all doors of the car. If lighting strikes the car, (or live current wire falls on car) electrostatic shielding develops on the outer surface of the car and we are safe inside the car.
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