A charged point is spread in a very thin uniform layer over

A charged point is spread in a very thin uniform layer over the surface of a plastic sphere of diameter 20cm,giving it a charge of -10.0 micro coulonA.Find the electric field outside the paint layer.b.Find the electric field 8 cm outside the surface of the paint layer?

Solution

(a)

E = (9 x 10⁹) (- 10 x 10^-6) / (10 x 10^-2)²

= 0.9 x 10⁷ N / C

(b)

E = (9 x 10⁹) (- 10 x 10^-6) / (18 x 10^-2)²

= 0.277 x 10⁷ N / C