A 74.5 kg ice skater moving to the right with a velocity of 2.62 m/s throws a 0.21 kg snowball to the right with a velocity of 23.8 m/s relative to the ground.

(a) What is the velocity of the ice skater after throwing the snowball? Disregard the friction between the skates and the ice.
1 m/s to the right
(b) A second skater initially at rest with a mass of 63.00 kg catches the snowball. What is the velocity of the second skater after catching the snowball in a perfectly inelastic collision?
2 m/s to the right

1 answer

(a) Using a coordinate system fixed to the ground, apply momentum conservation as follows:
(74.5+0.21)*2.62 = V'*74.5 + 0.21*23.8

V' is the skater's final velocity.
195.74 = 74.5 V' + 4.998

V' = 2.56 m/s
(positive is to the right)

(b) Apply momentum conservation again
0.21*23.8 = (63.00 + 0.21) V
Solve for V