Question

two carts with masses of 10.0kg and 2.5kg move in opposite directions on a frictionless track, with speeds of 6.0m/s and 3.0m/s respectively. The carts stick together after colliding head on. Find the final speed of the two cars

Answer 1

Momentum conservation applies.

10*6-2.5*3= 12.5(V)
solve for V

Answer 2

4.2