An experimental rocket sled on a level, frictionless track has a mass of 1.4 X 104 kg. It propels itself by expelling gases from its rocket engines at a rate of 10 kg/s, at an exhaust speed of 2.5 × 104 m/s relative to the rocket. For how many seconds must the engines burn if the sled is to acquire a speed of 5.0 X 10¹ m/s starting from rest? You may ignore the small decrease in mass of the sled and the small speed of the rocket compared to the exhaust gas.

An experimental rocket sled on a level, frictionless track has a mass of 1.4 X 104 kg. It propels itself by expelling gases from its rocket engines at a rate of 10 kg/s, at an exhaust speed of 2.5 × 104 m/s relative to the rocket. For how many seconds must the engines burn if the sled is to acquire a speed of 5.0 X 10¹ m/s starting from rest? You may ignore the small decrease in mass of the sled and the small speed of the rocket compared to the exhaust gas.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter8: Momentum And Collisions

Section: Chapter Questions

Problem 47P: A model rocket engine has an average thrust of 5.26 N. It has an initial mass of 25.5 g, which...

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