A physicist found that a force of 1.32 N was measured between two charged spheres. The distance between the spheres was 95 cm. Calculate the force between the two spheres when the distance was increased to 1.25 m?

The electric force (and the gravitational force too) is inversely proportional

to the square of the distance between the objects involved.

In this question, the distance is increased by a factor of (1.25/0.95).

So the electric force will change by the factor of (0.95/1.25) ².

The new force is

(1.32 N) · (0.95/1.25) ² = 0.762 ... newton (rounded)