umm... that's not it... it's suppose to be relative to the cart.. i know this cause i did something similar to urs and i got it wrong..
and by the way the mass of balls are seperate...
Momentum Poblem.. Need help!
A 1.5 kg cart is propelled forward by a series of 85g balls being ejected from the rear of the cart with a speed of 3.5 m/s relative to the cart. Calculate the speed of the cart after three balls have been ejected. Compare this to the speed of the cart if it had...