**1. The problem statement, all variables and given/known data**

Two charges of equal magnitude Q are held a distance d apart. Consider only points on the line passing through both charges.

If the two charges have the same sign, find the location of all points (if there are any) at which the potential (relative to infinity) is zero.

a) Midway between the charges

b) At the points, where the charges are

c) There are no such points

**2. Relevant equations**

V = k(Q/r)

**3. The attempt at a solution**

I know the answer is not a. But because of the "relative to infinity" statement, I’m not sure about b or c.

For b, the equation would look like: V = k(Q/0) + k(Q/d). I don’t know what to do with the division by 0.

I’m inclined to go with c, but I would like some support please.

http://ift.tt/1q9kalq