An engine is used to pull a train of two cars out of a mine. The floor of the mine slopes upward at an angle of 30°. Each car has a mass of 104 kg and normally travels without friction on the tracks. The engine can exert a maximum force of 1.5 · 105 N on car A. a. The engine first accelerates the cars from rest by exerting its maximum force. What is the acceleration of the cars ? b. Once the train has reached a reasonable speed, the engineer throttles back so that they continue at a constant speed. Now what force does the engine exert on car A? c. What is the tension in the massless, straight chain connecting cars A and B while they are travelling at a constant speed? d. If the engineer again throttles back so that the force exerted by the engine on car A decreases at the constant rate of 3N per second, how long before the train stops moving up the track? Assume the original speed was 3 meters per second.

An engine is used to pull a train of two cars out of a mine. The floor of the mine slopes upward at an angle of 30°. Each car has a mass of 104 kg and normally travels without friction on the tracks. The engine can exert a maximum force of 1.5 · 105 N on car A. a. The engine first accelerates the cars from rest by exerting its maximum force. What is the acceleration of the cars ? b. Once the train has reached a reasonable speed, the engineer throttles back so that they continue at a constant speed. Now what force does the engine exert on car A? c. What is the tension in the massless, straight chain connecting cars A and B while they are travelling at a constant speed? d. If the engineer again throttles back so that the force exerted by the engine on car A decreases at the constant rate of 3N per second, how long before the train stops moving up the track? Assume the original speed was 3 meters per second.

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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