Newton's 3rd Law: The Rocket & Ground Reaction Force

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SUMMARY

Newton's 3rd Law states that for every action, there is an equal and opposite reaction. In the context of rocket propulsion, the rocket's engines push down on the ground, resulting in an upward force from the ground. However, the primary action is the rocket expelling exhaust gases, which propels it forward in space. This discussion clarifies misconceptions about rocket functionality in a vacuum, emphasizing that rockets operate by pushing against ejected particles, not against a physical surface.

PREREQUISITES
  • Understanding of Newton's Laws of Motion
  • Basic principles of rocket propulsion
  • Knowledge of action-reaction forces
  • Familiarity with the concept of thrust in aerospace engineering
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  • Research the mechanics of rocket propulsion in a vacuum
  • Explore the principles of thrust and drag in aerospace applications
  • Study real-world examples of rocket launches and their physics
  • Learn about the historical misconceptions regarding rockets in space
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Aerospace engineers, physics students, educators, and anyone interested in the principles of rocket science and Newtonian physics.

bland
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I notice on http://teachertech.rice.edu/Participants/louviere/Newton/law3.html at Rice University that regarding Newton's 3rd law it says that...

The rocket's action is to push down on the ground with the force of its powerful engines, and the reaction is that the ground pushes the rocket upwards with an equal force.

Surely this is a fundamental error. Isn't the rocket pushing against the ejected particles?
 
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