Reply With QuoteIf the conveyor/treadmill were on an incline, do you imagine it can move fast enough uphill to prevent someone from skateboarding down?
What is speed? Displacement divided by time.
If there is no displacement, there is no speed and no airflow over the wing.
However, if there is displacement, there is speed and there is airflow over the wing.
If the speed is great enough to cause enough air flow over the wing to create lift, the plane will take off.
If the conveyor/treadmill were on an incline, do you imagine it can move fast enough uphill to prevent someone from skateboarding down?
If the conveyor/treadmill were on an incline, do you imagine it can move fast enough uphill to prevent someone from skateboarding down?
Is the skateboard motorized
What seems to stump most people is the fact that the wheels are not the driving force behind an airplanes forward thrust so the wheels spin has no relation to the engine speed of the plane whatsoever.
However you want to look at it, the airplane moves forward to activate the treadmill speed and the freewheeling rotation of the wheels absorb the impact of the treadmill.
Have a nice flight
What seems to stump most people is the fact that the wheels are not the driving force behind an airplanes forward thrust so the wheels spin has no relation to the engine speed of the plane whatsoever.
However you want to look at it, the airplane moves forward to activate the treadmill speed and the freewheeling rotation of the wheels absorb the impact of the treadmill.
Have a nice flight
I understand this concept and agree that if you were able to keep the plane stationary (a teather?) while moving the belt below it, and get the wheel speed to...whatever you like, then regular thrust would equal roughly regular movement and then take off.
The problem is planes cant take off with a teather attached, so sitting on the belt with the wheels not moving and weight sitting atop when the belt turns on the plane moves backwards, thus needing thrust to overcome backwards movement, and get back to just a stop, once making it back to a stop speed the engine will have to continue to provide thrust to keep the plane stationary. It will require additional thrust to move forward for flight. Assuming the plane does not need 100% of its power to take off on a regular runway it is still possible to fly, pending the belt speed and length of time spent moving backwards (enough to get plane to belt speed)
Does a rocket need wind to fly?
Does a rocket need wind to fly?
yes...a space ship does not
OMG
plane moves backwards, thus needing thrust to overcome backwards movement
Let me state this again;
The problem says "it adjusts its speed to match the plane's speed but in the opposite direction".
Therefore if the plane (fuselage) is not moving, then the treadmill is not moving. If the plane is moving at 10mph then treadmill is moving at 10mph. if the plane slows down, the tread mill slows down. If the plane speeds up the treadmill speeds up. If the plane stops, then the treadmill stops.
According to the problem as stated, there is no way the plane can move backwards.
http://i76.photobucket.com/albums/j4...4/images-1.jpg
who needs a treadmill ??
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