1. The problem statement, all variables and given/known data Two point charges are separated by a distance r. If the separation is reduced by a factor of 3/2, by what factor does the electric potential between them change? A. 3/2 B. 2/3 C. 9/4 D. 4/9 E. Sqrt(3/2) 2. Relevant equations 3. The attempt at a solution Honestly I couldn't think of any formula involving separation of 2 point charges and the electric potential between them. Reading a little more on electric potential, I find that U=Ed but then I'm not sure whether the strength of the electric field remain constant when we change the distance between two point charges.