# The electric field strength just above one face of a copper penny is 1950. What is the surface...

## Question:

The electric field strength just above one face of a copper penny is 1950. What is the surface charge density on this face of the penny?

## Electric Field:

The electric field due to a charge in a region is defined as the force experienced by another charge present in that region.

Given:

• Electric field, {eq}E=1950 \ \rm N/C {/eq}

The electric field on the surface of the penny will be zero because air is a bad conductor of electricity being a poor dielectric of the dielectric constant of 1 having a value of electric breakdown (magnitude of electric field required for the motion of charge .i.e., current) and an electric field near the surface will not affect the material of the penny.

And surface charge density is given as

{eq}\sigma=\frac{q}{A} {/eq} where q is the excess charge which is zero on the surface of a penny.

Therefore, surface charge density is zero.