help!! Collisions between astroids??? 1. The problem statement, all variables and given/known data In outer space a rock with mass 6 kg, and velocity < 4200, -3100, 3000 > m/s, struck a rock with mass 18 kg and velocity < 250, -280, 360 > m/s. After the collision, the 6 kg rock's velocity is < 3700, -2500, 3500 > m/s. What is the final velocity of the 18 kg rock? "need the x, y, and z component" What is the change in the internal energy of the rocks? "in J" 3. The attempt at a solution i used P1^2 = P3^2 + P4^2 + 2P3P4cos A where A is the angle between the particles. I did not know what A was so i assumed that it was 90 degrees like it would be in an elastic collision with identical masses, but that is a bad assumption becasue the masses are not equal. so now im stuck. any help or a formula would be great thanks all!!