There were two parts to this problem
a) if you do 12 J of work to push 0.001 C of charge from point A to point B in an electric field, what is the voltage difference between A and B?
I already solved this part, I got [tex]\Delta[/tex]V=12,000 V
b) When the charge is released, what will be its kinetic energy as it flies back past its starting point A? What principle guides your answer?
Here i have absolutely no idea what to do.
The Attempt at a Solution
I've gotten through part A but i have no idea how to approach part B.