PEi = GM2M/8R = -GM^2/4R and PEf = GM2M/3R = -2GM^2/3R
delta PE = Final - initial
make them so that they have common base which is -8GM^2/12R + 3GM^2/12R
Homework Statement
Two spheres having masses M (sphere 1) and 2M (sphere 2) and radii R and 2R, respectively, are released from rest when the distance between their centers is 8R.
How fast will sphere 1 be moving when they collide? Assume that the two spheres interact only with each other...