Brain teaser

[Scro]

I got in on this debate on another forum, just wanted to see what y'all had to say about it.

A plane is standing on a runway that can move (some sort of band conveyor). The plane moves in one direction, while the conveyor moves in the opposite direction. This conveyor has a control system that tracks the plane speed and tunes the speed of the conveyor to be exactly the same, but in the opposite direction. Can the plane take off?

[k4f5x0r]

Well planes dont actually need contact with the ground to move. They use the jet engines to move forward.

So if its actually moving, but the conveyor is matching its speed, i would guess that it would take off once it hits optimal speed.

[DnB_racing]

as long as there is the right amount of wind pressures and resistance under and over the wings,as ists the differance of pressures that cause the lift

[quadbod]

Isn't it all about low and high pressure across the wings? If so them it ain't going anywhere on a belt!

[Hondamaster5505]

They tested this on mythbusters...:ermm: lol.

Of course it will take off. The planes run by either a propeller or jet engine.. which is NOT in contact with the wheels. The engine has no effect on the wheels, they'll like shopping cart wheels.

Therefore, the thrust from the plane still pushes it foward, but the wheels just spin faster since the belt is going the opposite way. But the plane will get moving since the wheels don't hold it back.

[finsteratv]

no because there will be no lift on the wings from staying in the same spot.

[Hondamaster5505]

Originally posted by finsteratv
no because there will be no lift on the wings from staying in the same spot.

It won't stay in the same spot. The wheels don't connect to the motor in any which way. The plane will accelerate and take off like it's on pavement.

[Hondamaster5505]

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[tri5ron]

it's all right here

http://mythbustersresults.com/episode97

[finsteratv]

guess i was wrong
haha that adam guy is always so happy when they discover somthing

[yam450_53]

Of course it will take off. It will still go forward since the turbine engines are pushing it forward, the wheels only provide a weak resistance to the movement before take off. It's a physics principle.

[nskukalek79]

The plane will be sitting still in one spot if the conveyor is at the same speed....and if the plane is not moving at all it's definitely not going to take off...that plane on mythbusters is moving, thats a different scenario

[Hondamaster5505]

Originally posted by nskukalek79
The plane will be sitting still in one spot if the conveyor is at the same speed....and if the plane is not moving at all it's definitely not going to take off...that plane on mythbusters is moving, thats a different scenario

The plane would NOT be sitting still. The wheels are NOT in ANY WAY connected to the planes engines. It will take off like regular pavement, just the wheels will be going twice as fast.

[nskukalek79]

i couldn't picture it until just now...my bad....tis true it will take off and move....your right