Question

A charged paint is spread in a very thin uniform layer over the surface of a plastic sphere of diameter 19.0{\rm cm} , giving it a charge of -13.0\mu {\rm C}

Find the electric field just outside the paint layer.
Find the electric field 8.50{\rm cm} outside the surface of the paint layer.

Answer 1

total q=13microC

E=k*totalcharge/radius

Answer 2

12