Thanks a lot, this should really help. What I don't understand though is that if the charges are now (q1-q2)/2, then why is the force k(q1-q2)^2/d^2? Where did the 2 in the denominator go?
Homework Statement
Two identical small metal spheres initially carry charges q_1 and q_2. When they're x=1.0m apart, they experience a 2.5N attractive force. Then they're brought together so charge moves from one to the other until they have the same net charge. They're again placed x=1.0m...