Find the greatest surface charge density that can exist on a conductor before dielectric breakdown of the air occurs. the dielectric strength of the air is 3 × 106 v/m and permittivity of free space is 8.85 × 10−12 c 2 /n · m2 .

Explanation:

The electric field on the surface of a conductor is given by:

Here is the surface charge density and the permittivity of free space. Thus, the highest surface charge density that can exist in a conductor is given by the value of the dielectric breakdown of the air multiplied by the permittivity of free space:

e/c, where e is its total energy

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