A blue puck with mass 0.0400 kilogram, sliding with a velocity of magnitude 0.200 m/s on a frictionless, horizontal air table makes a perfectly elastic, head-on collision with a red puck with mass m, initially at rest. After the collision, the velocity of the blue puck is 0.050 m/s in the similar direction as its initial velocity.
(a) Determine the velocity (magnitude and direction) of the red puck after the collision?
(b) Determine the mass m of the red puck.