Please help I've attempted this problem various ways and I can't seem to get the correct answer.

A 69.0 kg person throws a 0.0410 kg snowball forward with a ground speed of 35.0 m/s. A second person, with a mass of 60.0 kg, catches the snowball. Both people are on skates. The first person is initially moving forward with a speed of 2.00 m/s, and the second person is initially at rest. What are the velocities of the two people after the snowball is exchanged? Disregard the friction between the skates and the ice.

1 answer

This is a conservation of momentum problem. You have to do it in two steps, since there are two unknowns.

V1i = first person's initial velocity = 2.00 m/s
V1f = first person's final velocity = ?
m = snowball mass = 0.041 kg
M1 = first person's mass = 69 kg
M2 = second person's mass = 60 kg
V2i = second person's initial velocity = 0
Vrf = second person's final velocity = ?
v = snowball ground speed in flight = 35 m/s

(M1+m)*V1i = M1*V1f + m*v
Vif = (69.041/69)*2.00 - (0.041/69)*35
= 2.001 - 0.021 = 1.98 m/s

For person no. 2, let the initial state be with the snowball flying, and the final state after it is caught.
m*v = (M2+m)*V2f

V2f = (0.041)*35/(60.041)
= 0.024 m/s