Question

a) Why does Earth have an electric field surrounding it?

b) Where is the electric field around Earth the strongest?

Answer 1

a)The surface of earth has got charge indeed a strong charge which is considered to be uniformly distributed over its surface. This charge actually comes from sun.

Modelling the earth as a uniformly sphere, the electric field of earth can be determined.

Its estimated that the surface has got 500 kC of the negative charge.

At the surface electric field is roughly estimated to be between 65 N/C to 150 N/C.

b)The electric field is strongest near the surface of the earth and then it drops exponentially with height since the conductivity of atmosphere increase later with height.