A freight train consists of a 8.33E+05-kg engine followed by 50 cars with average masses of 5.08E+05 kg. The engine exerts a forward force of 3.33E+06 N (applied to the first car of the train), against a force of friction of 7.50E+05 N which is evenly distributed over all the cars (not the engines).
What is the magnitude of the force in the coupling between the 27th and 28th cars (this is the force each exerts on the other),
assuming all cars have the same mass and that friction is evenly distributed among all of the cars and engines?
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