Question

two unlike charges attract each other with a force 10N . if the distance between them is doubled the force between them is

Answer 1

Let the initial force =F The force between two unlike  Charges=9×10^9×q1q2/r^2 eq2 If the force is doubled  2F=9×10^9×q1q2/R^2-eq 1 -Eq1/eq2 we get R=r/root(2){r^1/2}