Question

5. An object has a momentum of 4,000 kg-m/s and a mass of 115 kg. It crashes into another object that has a mass of 100 kg, and the two objects stick together. If the momentum is conserved, what is the new velocity of the combined object? Round to the nearest hundredth.

A. 34.78 m/s
B. 15.82 m/s
C. 69.56 m/s
D. 18.60 m/s​

Answer 1

D. 18.60

Step-by-step explanation:

By the law of conservation, the momentum is neither loss nor gained but instead transfered. When they crash into each other, and stick, they combine to create a total mass of 215 kg. Since the momentum is transfered, the two objects, combined, have a total momentum of 4000 kg-m/s. We know that momentum equals mass times velocity. You then divide 4000 by 215 and get approximately 18.6 m/s