VERY hard question...Will the plane take off?

Question

A jet powered plane is standing on a movable runway (something like a giant treadmill). As the plane moves the treadmill moves but in the opposite direction. The treadmill has a system that tracks the speed of the plane and matches it exactly in the opposite direction.

The question is: Will the plane take off or not?

All Forces such as wind resistance and friction are not counted.

Think carefully...

Answer 1

yes, it will take off because it will not stay on the treadmill. Unlike most land based vehicle which turns the wheels to move the vehicle a jet engine pushes the jet relative to the surrounding air. As the wings move through the air lift is generated. If the tread mill were long enough the jet would lift off while still on the treadmill otherwise it would move off the treadmill onto terrafirma.

Answer 2

This question seems to invite intense disagreement due to its ambiguity. The problem lies in defining the "speed of the plane." Is the speed of the plane that the runway tracks measured in relation to the runway or in relation to the stationary ground?

If the runway exactly negates the speed of the plane relative to the runway, then the plane's speed relative to the ground will always be exactly zero and the plane will not take off.

If the runway exactly negates the speed of the plane relative to the ground, then when the plane is traveling at a speed of, say, 100 mph as relative to the ground, the runway will be going backwards at 100 mph and the speed of the plane relative to the runway will be 200 mph. The speed of the plane relative to the runway will always be twice the speed relative to the ground. Therefore, the plane will eventually gain enought speed to take off.
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Incidently, the fact that a jet plane pushes off against its own exhaust rather than gains speed like a car does from wheels that are powered to rotate has NOTHING to do with anything.

Answer 3

Ok, the only thing that makes the plane take off is the property of lift. Lift is caused by air moving over the top of the wing. If this treadmill goes keeps the plane in the same exact location, there is no speed at all, therefore no lift, therefore no takeoff.

Also a plane's engine never turns its wheels, it pushes the air behind it, so no matter how fast this treadmill is, the engine would push this plane off the front of this treadmill

no, impossible

Answer 4

I think the plane should take off..In order to generate lift all that is required is for the wind to flow over and under the inclined wing. The situation you proposed easily satisfies this condition

If the body is shaped, moved, or inclined in such a way as to produce a net deflection or turning of the flow, the local velocity is changed in magnitude, direction, or both. Changing the velocity creates a net force on the body which lifts the body and helps take off
Wind resistance is an absolute must for generating lift..No wind No take off..

Answer 5

A jet engine pushes against its own exhaust gas, not against the runway. It will accelerate 'til it goes off the end of the treadmill; then it'll stick in the mud.

Answer 6

Yes. If the plane is moving then that means it is going forward which means air is passing over and under its wings which means it has lift which means it takes off.

Answer 7

The plane is stationary vs. the air around it. It sits there unlofted.

Answer 8

Yes.