a 2000kg car traveling east at 24m/sec enters an icy (frictionless) intersection and collides with a 3600kg truck traveling south at 10 m/sec. If they become coupled together in the collision, what is their velocity immediately after impact?

Answer 1

The final momentum is the vector sum of the two initial momenta, which are perpendicular in this case. The eastward component is 48,000 and the southward component is 36,000 kg m/s. Note that you have a 3:4:5 right triangle. Divide the resultant momentum of 60,000 kg m/s by the combined mass for the final speed.