[tpaine]

A common misconception by laymen is that the force is derived from "pushing against" the water/air as in pushing against a wall. In reality, the force is derived from the acceleration of the water/air. The force would be the same in a vacuum for the same amount of water/air accelerated even though there would be no air/water to push against.
78 -cinFLA-


The issue:

"The propellor or the jet engine of an aircraft push air backwards to propel the aircraft forward. A ship or boat propellor does the same thing with water. On Earth there is always air or water available to push against. But a rocket in space has nothing to push against, and so it needs to carry propellant to eject in place of air or water."
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Perfectly simple point made above.
-- If you are on the ground you can push against it to move.
-- If you are in the water you can push against it to move.
--- If you are in the air you can push against it to move.
--- If you are in space you can't push against it to move, you must eject something away from you.

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Now you claim:

"This all started because I took exception to the statement that a "propellor pushes" against the air/water."
-cin-

As we see above, you can't keep your story straight on ANYthing.

[cinFLA]

Perhaps you remember who wrote this about you.

"Hah! That's rich. "Personal attacks and insults" are your first and last names and inflicting pain is your game. Abuse reports from people with unclean hands are not taken seriously. If you want to be taken seriously on this forum you might think about cleaning up your act."