Question

The electrostatic force between two charges is 3. 8 N. If the distance between the two charges is tripled, what is the new electrostatic force acting between the charges?

Answer 1

F = K Q1 Q2 / R^2 force between 2 charges separated by R

F2 / F1 = (R1 / R2^2) dividing equations

F2 / F1 = (R1 / 3 R1)^2 = 1/3^2 = 1/9

The force would be reduced by a factor of 9

3.8 / 9 N = .42 N