Question

The small identical conducting sphere have charge of 2.0*E9 Coulomb and -0.5*E9 Coulomb respectively when they are placed 4cm apart what is the force between them.

Answer 1

The Coulomb’s law states

F=k |q_1 ||q_2 |/r^2

So

F=9×〖10〗^9×(2.0×〖10〗^9×0.5×〖10〗^9)/(0.04)^2

=5.63×〖10〗^30 N