Question

What is the mutual force of repulsion between two charged spheres 2 cm apart if the repulsive force for a 1 cm separation is 16 N?

Answer 1

The force of repulsion is directly proportional to the charges, but inversely proportional to the square of the distance.

Explanation:

This means that doubling the distance will reduce force by `2^2=4xx`.
So the repulsive force will be `16Ndiv 2^2=4N`