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

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Newton's 3rd Law states that for every action, there is an equal and opposite reaction, which is illustrated by a rocket pushing down on the ground and the ground pushing the rocket upwards. However, the discussion highlights a misconception that rockets only push against the ground, while they actually propel themselves by expelling exhaust gases. This clarification addresses the common belief that rockets cannot function in space due to the absence of a medium to push against. Historical corrections, such as those made by the New York Times, emphasize that rockets operate effectively in a vacuum by utilizing the reaction force from ejected particles. Understanding these principles is crucial for grasping rocket propulsion dynamics.
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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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