Plane on conveyer: Will it ever take off?
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From: 3rd bedroom on the right
Originally Posted by no_really,Dec 2 2005, 01:04 PM
you, sir, should become an aeronautical engineer. Your grasp of the complexities of flight are unparalleled. Don't let anyone tell you different - they are just jealous of your unmatched intellect. My God, it must be hell for you, such a mind surrounded by the likes of the rest of us mental incompetents. You cranium must be gigantic! I can only thank you for having pity on us mere mortals, gracing us with your wisdom without any sense of pity or condescencion. 
Wow that pot's a racist mofo 
Go get laid pal
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From: Pittsburgh..south side..
Originally Posted by Tedow,Dec 1 2005, 09:02 PM
Actually, yes it will. The trick is that the plane's engines are not pushing against the ground, as a car would. The force comes from the air, so the plane moves forward as usual...the presence of the moving ground plane is completely irrelevant. Well, okay, the plane's wheels will spin twice as fast as usual, but that's all. Plane takes off.
And for the record, jet engines don't operate by "pushing", they are propelled forward more by the act of throwing the air out the back, like if you fired a shotgun, while sitting on a barstool. You'd fly back the opposite way, not because the bullet pushed the air, but because of conservation of momentum.
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From: Toronto
Originally Posted by no_really,Dec 1 2005, 06:04 PM
you, sir, should become an aeronautical engineer. Your grasp of the complexities of flight are unparalleled. Don't let anyone tell you different - they are just jealous of your unmatched intellect. My God, it must be hell for you, such a mind surrounded by the likes of the rest of us mental incompetents. You cranium must be gigantic! I can only thank you for having pity on us mere mortals, gracing us with your wisdom without any sense of pity or condescencion.
No need to say anything further.
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From: Arlington, VA
Originally Posted by dcak,Dec 1 2005, 09:12 PM
The engines will have thrust, yes, but since the plane will not be accelerating through the fluid atmosphere, there will be no lift on the wings, hence no flight.
And for the record, jet engines don't operate by "pushing", they are propelled forward more by the act of throwing the air out the back, like if you fired a shotgun, while sitting on a barstool. You'd fly back the opposite way, not because the bullet pushed the air, but because of conservation of momentum.
And for the record, jet engines don't operate by "pushing", they are propelled forward more by the act of throwing the air out the back, like if you fired a shotgun, while sitting on a barstool. You'd fly back the opposite way, not because the bullet pushed the air, but because of conservation of momentum.
Um, why wouldn't the plane be accelerating through the fluid atmosphere? Engine sucks air in the front, accelerates it out the back, generating thrust. Thrust makes the plane move forward, resisted only by drag. The only force involving the wheels is the one keeping the plane from falling onto the ground. Draw a control volume around the plane, you'll get it.Let me know how the crow tastes.
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From: Doh!!
Tedow is right given the problem exactly as it is. the fact that the conveyor is moving doesn't change the fact that the plane will move forward with respect to the GROUND (and the still air). the conveyor belt can go at 10mph or 10000mph and it still wouldn't matter b/c the wheels of the plane is freely spinning.
you guys are assuming that since the conveyor is turning it prevents the plane from moving forward (would be true if this were a car b/c the acceleration of the car depends on the wheels turning). the plane's accel depends on the engine's thrust.
put it another way, if you coat coat the tires with teflon put the car on an icy lake, gunning the engine would result only in spinning the tires. doing the same with the plane would result in take off.
becareful arguing plane problems with a guy who has SR71 as his av
you guys are assuming that since the conveyor is turning it prevents the plane from moving forward (would be true if this were a car b/c the acceleration of the car depends on the wheels turning). the plane's accel depends on the engine's thrust.
put it another way, if you coat coat the tires with teflon put the car on an icy lake, gunning the engine would result only in spinning the tires. doing the same with the plane would result in take off.
becareful arguing plane problems with a guy who has SR71 as his av
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From: Arlington, VA
Originally Posted by S2020,Dec 1 2005, 10:10 PM
becareful arguing plane problems with a guy who has SR71 as his av
Bingo.By the way, I was amazed when I did a Google search on "plane conveyer." Literally hundreds of pages of arguments over whether the plane flies or not.
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From: La Habra
It is a poorly worded puzzle I have seen before. The plane takes off because it IS moving in the air. Just because the conveyor is moving in the opposite direction doesn't mean the plane is not also moving in its forward direction.
