A SpaceX rocket with an initial mass of m0 uses its engines to hover, stationary, just above the ground. (a) Write down a differential equation for the rocket’s mass using the condition that the thrust must balance the force of gravity. Assume the exhaust speed vex is a constant. (b) The rocket burns fuel and hovers until the final mass is mf . Solve for the amount of time it is able to hover. (c) Calculate the hover time for a rocket that burns an amount of fuel equal to 30% of its initial mass, with an exhaust speed of 2000 m/s.

A SpaceX rocket with an initial mass of m0 uses its engines to hover, stationary, just above the ground. (a) Write down a differential equation for the rocket’s mass using the condition that the thrust must balance the force of gravity. Assume the exhaust speed vex is a constant. (b) The rocket burns fuel and hovers until the final mass is mf . Solve for the amount of time it is able to hover. (c) Calculate the hover time for a rocket that burns an amount of fuel equal to 30% of its initial mass, with an exhaust speed of 2000 m/s.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter5: Newton's Law Of Motion

Section: Chapter Questions

Problem 30P: If the rocket sled shown in the previous problem starts with only one rocket burning, what is the...

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