Two baseballs, each with a mass of 0.158 kg, are separated by a distance of 400 m in outer space. If the balls are released from rest, what speed do they have when their separation has decreased to 270 m? Ignore the gravitational effects from any other objects. I keep on using the conservation of energy equation, but nothing seems to give, I feel like i'm missing a step, Please help... This is what I've done so far Ei=Ef 1/2mvi^2-(Gm1m2/ri)=1/2mvf^2-(Gm1m2/rf) if this is the right equation.... KEi obviously = 0, how to I get rid of the mass(m) in the KEf, I can't cancel it out since there are 2 masses involved, am I right? value for G = 6.67x10^-11 Thanks for the help.