Two identical conducting spheres are placed with their centers 0.30 m apart. One is given a charge

Question:

Two identical conducting spheres are placed with their centers 0.30 m apart. One is given a charge of 12 × 10−9 C, the other a charge of −18 − 10−9 C.
(a) Find the electrostatic force exerted on one sphere by the other.
(b) The spheres are connected by a conducting wire. Find the electrostatic force between the two after equilibrium is reached.