A 3800 kg open railroad car coasts along with a constant speed of 8.60 m/s on a level track. Snow begins to fall vertically and fills the car at a rate of 3.50 kg/min. ignoring friction with the tracks what is the speed of the car after 90.0 minutes?

Answer 1

momentuminitial=momentumfinal

3800*8.60=(3800+3.50*time)v(t)
solve for v(t) for t=90min

Answer 2

.088

Answer 3

Correct me if I'm wrong, but...
Momentum before = Momentum after
mv(before)=m'v'(after)
(mass of train before snow)(velocity of train before snow)=m'v'
(3,800 kg)(8.6 m/s)=(3,800 kg + added weight of snow)(v')
32,680=(3,800+315)(v')
32,680=4115(v')
v'= 7.94 m/s