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Does the plane take off?
Posted 27 August 2007 - 04:29 AM
Now take the same situation and replace the jet plane with a propeller plane. Does the plane take off?
Posted 27 August 2007 - 06:03 AM
Answer for a propeller plane:
An airplane takes off when its wings generate a lift force greater than its weight. Lift force is determined by air speed. A backward-running treadmill will not impede the plane's forward motion, nor limit its air speed, only make its wheels spin twice as fast!
But what if an airplane's engine drove its wheels? Then the answer would be No. It could not achieve forward motion nor generate lift.
That would be an interesting kind of airplane - after it took off it would become a glider!
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