U = k*Q*q/r,
but I don't know the radius between the two spheres at the start.
EDIT: I just realized that since they start so far apart they aren't affecting each other, I don't need the potential at the start, only at the end. So it'd just be 1/2*m*v^2 = Ufinal, right? Using the combined...
So, assuming you need just enough energy to get the two to stop after colliding, the final Kinetic Energy should be zero, so Uinitial + 1/2*m*v^2 = Ufinal?
What's the equation for potential energy in this case?
Homework Statement
A charge of 3.0 μC is distributed uniformly throughout the volume of plastic
sphere with a radius of 10.0 cm. An identical plastic sphere with charge 3.0 μC
is shot directly at the center of the first sphere, from very far away. The mass
of each sphere is 5.0 X 10^-5...