Re: Physics graduate from Daryn\'s alma mater\'s answer
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How can the plane move and the wheels stand still?
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The wheels do not move while the plane is flying. My point is forward movement of the plane is not driven by the wheels in any way, shape, or form.
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Oh ok, I don't think anybody is having any trouble with that part. The issue is that it doesn't matter if the plane is moving the wheels or the wheels are moving the plane, (in fact neither is happening).
As the plane moves forward the wheels must move faster than the conveyor belt is moving, even if they are just being taken along for the ride.
Just like pushing a skateboard forward on a treadmill. The only time the wheel speed equals the treadmill speed is when you are holding the skateboard stationary.
Edit: To illustrate imagine the skateboard on a treadmill moving at 1m/s. After one second the wheel will have covered 1m of treadmill track.
Wheel speed 1m/s
Treadmill speed: 1m/s
Skateboard speed: 0m/s
If you push the skateboard forward during that second at a rate of 1m/s the wheel will have covered 2m of track.
Wheel speed 2m/s
Treadmill speed: 1m/s
Skateboard speed: 1m/s
Therefore in order for the skateboard to move forward, wheel speed must be greater than treadmill speed and the conditions of the OP can't be met.
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