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kccustom

Can the plane take off?

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Guest navinjohnson

I know that it is simple, but I'm just trying to help out the few that need a better understanding of physics.

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Guest LookBackX2
You're all reading way too much into it.

 

Everything has to to do with the conveyor belt canceling out the speed at which the plane tries go.

 

The plane is stationary

 

plane stationary = no wind

 

no wind = no lift

 

no lift = no fly

 

It is not stated that the conveyor belt cancels out the speed the plane tries to go. It matches the speed at which the wheels turn. In order for the wheels to turn, the plane has to initially move.

 

If the plane beginning to move triggers the belt to move thus matching the tires rotation, how can the plane be stationary???

 

 

Furthur, tires rotate against a runway at a finite rate when a plane reaches liftoff. This will vary depending on wind speed and direction. Whatever that number happens to be for any plane, double it and you have what speed the tires rotate with this belt under them. everything else still works just as it should.

 

The plane can not be stationary for this question to even make sense guys. Airplane tires are not driven, they are simply casters to keep the fuselage off the tarmac/conveyor belt. Any rotation in the tires is a RESULT of the plane no longer being stationary.

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I think this is a stupid question. I've never heard of 200 mph conveyor belt. Even less of one that can match the speed of a wheel of an airplane exactly. A pointless exercise in nothing! It would be impossible to match every little change in rotational velocity of the wheel and if it could not, the resulting friction would result in a massive torque on the plane and the belt. Even if it could, because totally frictious surface is impossible. Anyway, here is the answer to the stupid question:

 

The solution comes from the fact that unlike the wheels of a car, the wheels of an aircraft are not motorised and that the aircraft's forward motion relative to the ground is created by the thrust of its engine(s), not the spinning of its wheels. With the treadmill moving in the opposite direction to the plane but at the same speed as the aircraft is moving relative to the rest of the world, the plane still takes off as normal, but with its wheels spinning at twice the speed they would otherwise be spinning at.

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I think this is a stupid question. I've never heard of 200 mph conveyor belt. Even less of one that can match the speed of a wheel of an airplane exactly. A pointless exercise in nothing! It would be impossible to match every little change in rotational velocity of the wheel and if it could not, the resulting friction would result in a massive torque on the plane and the belt. Even if it could, because totally frictious surface is impossible. Anyway, here is the answer to the stupid question:

 

Uh, they exist, what do you think they test F1 aerodynamics on the sidewalk?

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Guest Gir
You're all reading way too much into it.

 

Everything has to to do with the conveyor belt canceling out the speed at which the plane tries go.

 

The plane is stationary

 

plane stationary = no wind

 

no wind = no lift

 

no lift = no fly

 

I agree.

 

I dissagree.

 

I believe the engines providing the thrust will propel the plane forward regardless of how fast the wheels/tires are spinning.

 

The only way i could see the plane not moving in a forward direction would be to tether it down.

 

 

Just my 2cents

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Guest navinjohnson

Unless that plane takes off, the force generated by the jet engines and the force generated by the engine of a car do the SAME THING they rotate the wheels of the vehicle because they both create a net torque on the wheels.

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Guest LookBackX2
Unless that plane takes off, the force generated by the jet engines and the force generated by the engine of a car do the SAME THING they rotate the wheels of the vehicle because they both create a net torque on the wheels.

 

That is a massive oversight as to what actually drives the two spinning wheels your comparing. Cars=driveshaft+torque. Airplane =tire to road friction with torque being a product of the reaction, not a consumable.

 

Edit: Off topic my bad. <--- More reason to followsuit.

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Guest navinjohnson

Last post. People who think this thing will fly I advice you to go back to school and take your physics classes again. Good Bye

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Rad I want to ask you a question that is a deviation of the original question. Your answer will be important to how I formulate my next response.

 

Instead of a plane we use a car. Our new goal is to cross a finish line at the end of the same conveyor used for the plane. Will the car cross the finish line?

 

Remember this is a hypothetical question and certain assumption may have to be made... like the conveyor matches the speed of the wheels perfectly because that is the obvious purpose of it in this question...

 

If the finish line is a fixed reference point not on the conveyor; then the car will never reach it. If it's a point on the conveyor, then the car will cross the finish.

 

Edit: this is my last post in this thread; merely to answer a question directed @ me; It may be wise for a mod to lock this thread

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