Question
Explain : Electrostatic shielding.
✓
Answer
→Consider a conductor with a cavity as shown in the figure.
→The shape and size of the cavity can be any.
→There is no charge in the cavity.
→ No matter what external field such a conductor is placed in the electric field in the cavity is zero.
→Even if the conductor is charged, all charges, reside only on the outer surface of conductor with cavity.
→Like this, there is no effect of the external electric field or electric charge on the cavity. which means the cavity remains shielded from outside charge and external electric field, which is known as electrostatic shielding.
→This effect can be made of use in protecting sensitive equipments from outside electrical influence.
→E.g. in monsoon season, if we are sitting in a car and lightening strikes, we should close the doors and windows of the car. By doing this, we happen to be in the cavity of car and we are protected due to electro static shielding.
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