Three identical train cars, coupled together, are rolling

Last updated: 7/31/2022

Three identical train cars, coupled together, are rolling east at speed vo. A fourth car traveling east at 200 catches up with the three and couples to make a four-car train. A moment later, the train cars hit a fifth car that was at rest on the tracks, and it couples to make a five-car train. ▼ Part A What is the speed of the five-car train? Express your answer in terms of v0.