A 10.0 g object moving to the right at 22.0 cm/s makes an elastic head-on collision with a 15.0 g object moving in the opposite direction at 32.0 cm/s. Find the velocity of each object after the collision. First, I converted the masses to kg and the velocities to m/s. I used m1v1i + m2v2i = m1v1f + m2v2f and solved for v1f in terms of v2f and plugged this into v1i - v2i = v2f - v1f to attempt to get v2f first (yes, I am converting back to cm/s) and I'm not getting the right answer... I don't understand what I'm doing wrong... Here's my numbers: .01(.22) + .015(.32) = .01v1f + (.015)v2f .007 = .01v1f + .015v2f v1f = (.007 - .015v2f)/.01 = .7 - 1.5v2f (.22) - (-.32) = v2f - v1f .54 = v2f - (.7 - 1.5v2f) .54 = v2f -.7 + 1.5v2f .61 = 2.5v2f v2f = .244 m/s = 24.4 cm/s This is due at 8:30 AM. EST tomorrow.