A Locomotive Is Pulling 9 Freight Cars, Each of Which $37,000 \mathrm {~kg}$

Short Answer

A locomotive is pulling 9 freight cars, each of which is loaded with the same weight. The mass of each loaded car is $37,000 \mathrm {~kg}$ and we can neglect friction on these 9 cars. If the train is accelerating forward at $0.81 \mathrm {~m} / \mathrm { s } ^ { 2 }$ on a level track, what is the tension in the coupling between the second and third cars? (The car nearest the locomotive is counted as the first car.)