A locomotive is pulling 17 freight cars, each of which is loaded with the same amount of weight. The mass of each freight car (with its load) is 37,000 kg. If the train is accelerating at 0.7 m/s2 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, and friction is negligible.)

Answer 1

The tension between cars 2 and 3 accelerates cars 3 through 17. That is a total of 15 cars.

F = M*a, with M = 15*37,000 = 555*10^3 kg
a = 0.7 m/s^2
Solve for F, in Newtons

Answer 2

388500