posted by Anonymous on .
A tennis player places a 54 kg ball machine on a frictionless surface. The machine fires a 0.057 kg tennis ball horizontally with a velocity of 38 m/s toward the north. What is the final velocity of the machine?
m/s to the south
momentum is conserved.
velocitymachine=-.057/54 * 38 North
and of course, -North is South