posted by Megan on .
Ann, a 66.1 kg person throws a 0.0460 kg snowball forward with a ground speed of 31.7 m/s. Billy, with a mass of 60.5 kg, catches the snowball. Both people are on skates. Ann is initially moving forward with a speed of 2.29 m/s, and Billy is initially at rest. After the snowball is exchanged (a) What is Ann’s velocity? (b) What is Billy’s velocity? Disregard friction between the skates and the ice.
m1=66.1 kg, v1=2.29 m/s
m2=0.046 kg, v2= 31.7 m/s
m3=60.5 kg, v3=0
The law of conservation of linear momentum
(m1+m2) •v1 =m1•u1 +m2•v2
u1= [(m1+m2) •v1- m2•v2]/m1 =
=[(66.1+0.046) •2.29 – 0.046•31.7]/66.1 = 2.269 m/s
u3= m2•v2/(m2+m3) =
I got the correct answer for the thrower, but for the catcher to find the second velocity, I follow the formula but it still counts it as wrong. What could I be doing wrong?