A freight train consists of two 8.00 x 104-kg engines and 45 cars with average masses of 5.00 x 104 kg. (a) What force (in N) must each engine exert backward on the track to accelerate the train at a rate of 4.00 x 10-2 m/s² if the force of friction is 7.20 x 105 N, assuming the engines exert identical forces? This is not a large frictional force for such a massive system. Rolling friction for trains is small, and consequently trains are very energy-efficient transportation systems. N (b) What is the force (in N) in the coupling between the 37th and 38th 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? N

A freight train consists of two 8.00 x 104-kg engines and 45 cars with average masses of 5.00 x 104 kg. (a) What force (in N) must each engine exert backward on the track to accelerate the train at a rate of 4.00 x 10-2 m/s² if the force of friction is 7.20 x 105 N, assuming the engines exert identical forces? This is not a large frictional force for such a massive system. Rolling friction for trains is small, and consequently trains are very energy-efficient transportation systems. N (b) What is the force (in N) in the coupling between the 37th and 38th 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? N

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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