Posted by **Chris** on Saturday, March 3, 2007 at 9:21pm.

In a game of pool the cue ball strikes another ball of the same mass and initially at rest. After the collision the cue ball moves at 3.50 m/s along a line making an angle of 22 degrees with its original direction of motion. and the second ball had a speed of 2 m/s. a)What is the angle between the direction of motion of the second ball and the original direction of motion of the cue ball?

b) What is the original speed of the cue ball?

c) Is Kinetic energy (of the center of mass, don't consider the rotation) conserved?

a) would I use theda= arc tan of something? I'm not completely sure what though.

b) What is the equation I would use?

c) I don't think the kinetic energy is conserved.

Thanks so much for helping. I really appreciate it!