I've been having some trouble with this problem: A hollow ball that has radius=X, has uniform volume charge density of [tex]\rho[/tex]. 1) Gauss's Law->Find electric field at .1X and 3X from the center 2)What is electric potential at .1X and 3X from center? 3) Find electric potential energy of charge q, with mass = m, when it is released 3X from center of the hollow ball. When it hits the ball, what is its speed? For 3, would I have to equate electric potential energy to kinetic energy, and then solve for velocity? Any tips would be much appreciated!