Question

Two charges have a distance that is 2m between them. The force acting on each will be F=100 N. What is the force between them if: the distance between them is doubled ?

a.
100 N

b.
50 N

c.
25 N

d.
12.5 N

Answer 1

The force between two charges is inversely proportional to the square of the distance between them (just like the gravitational force between two masses).

If the distance is doubled, the change in force is (1/2)² = 1/4 .

New F = (old F) x (1/4)

New F = 25 N

Pick choice - C .