The yolk of the egg is white, or the yolk of the egg are white?
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Originally posted by Walker View PostFrom the original question we don't even know if the engines are running.
This is how I took it. I didn’t think the engines were running. I was thinking they were trying to lift off with just the conveyor.
But in theory, the lift comes from the wings and air. The thrust causes forward momentum. If the wheels weren’t allowing the plane to move forward then no air would run across wings.
Perfect example. A car on a dyno. They are running at extreme rpm’s and going nowhere. Because no wind is running over them , they use a fan to force wind in order to cool the radiator. The car is running 100+ mph and going nowhere.
The same would happen to the plane. If the thrust overcame the speed of the conveyer belt then the question would be inaccurate. It says the speed of the conveyor belt is designed to match the speed if the plane wheels. We got to assume that’s infinite.
No momentum from plane = no wind = no lift on wings
Sent from my iPhone using Tapatalk ProLast edited by FLASH_OUTDOORS; 06-04-2023, 09:11 AM.
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Originally posted by wickll View PostThink about a float plane..
It doesn't have ( or need) wheels to provide the thrust. The prop does that. All the wheels do is prevent friction from slowing it down. (or providing another force to overcome).
Let’s say the plane needed to travel 60mph to lift off and it was going up stream on a river with water running the opposite direction at 60mph? That’s the same scenario as the question
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Originally posted by FLASH_OUTDOORS View PostThis is how I took it. I didn’t think the engines were running. I was thinking they were trying to lift off with just the conveyor.
But in theory, the lift comes from the wings and air. The thrust causes forward momentum. If the wheels weren’t allowing the plane to move forward then no air would run across wings.
Perfect example. A car on a dyno. They are running at extreme rpm’s and going nowhere. Because no wind is running over them , they use a fan to force wind in order to cool the radiator. The car is running 100+ mph and going nowhere.
The same would happen to the plane. If the thrust overcame the speed of the conveyer belt then the question would be inaccurate. It says the speed of the conveyor belt is designed to match the speed if the plane wheels. We got to assume that’s infinite.
No momentum from plane = no wind = no lift on wings
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The car on the dyno is strapped down. Ever see what happens when one comes loose? Plus the car on the dyno is driven by the wheels the plane isn’t.
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Originally posted by Old Bald Guy View PostWrong, if the conveyor is running the same speed as the wheels and the wheels aren’t moving the conveyor won’t be moving either.
The car on the dyno is strapped down. Ever see what happens when one comes loose? Plus the car on the dyno is driven by the wheels the plane isn’t.
Ok take the plane out of the equation. Just look at the wheels. If they roll forward at 5mph and the conveyor moves backwards at 5mph, how would they move? The question states that the conveyor EXACTLY matches the speed of the wheels. So as the wheels speed up the conveyor does as well. For the plane to travel forward it would need the have the wheels spin faster than the conveyor. According to the quest that’s not possible.
I’m thinking skate board on a tread mill. If you stand on one, the wheels are spinning at the speed set on the treadmill. You aren’t actually moving anywhere but the wheels are spinning forward as if you are. If you are pushed from behind you could move forward but that’s only because the treadmill is no longer “exactly matching the speed of the wheels”
Per the question if I was on a skateboard on a treadmill and someone pushed me from behind, the treadmill would speed up exactly matching the opposing force, therefore canceling it out.
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Originally posted by FLASH_OUTDOORS View PostOk take the plane out of the equation. Just look at the wheels. If they roll forward at 5mph and the conveyor moves backwards at 5mph, how would they move? The question states that the conveyor EXACTLY matches the speed of the wheels. So as the wheels speed up the conveyor does as well. For the plane to travel forward it would need the have the wheels spin faster than the conveyor. According to the quest that’s not possible.
I’m thinking skate board on a tread mill. If you stand on one, the wheels are spinning at the speed set on the treadmill. You aren’t actually moving anywhere but the wheels are spinning forward as if you are. If you are pushed from behind you could move forward but that’s only because the treadmill is no longer “exactly matching the speed of the wheels”
Per the question if I was on a skateboard on a treadmill and someone pushed me from behind, the treadmill would speed up exactly matching the opposing force, therefore canceling it out.
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Originally posted by FLASH_OUTDOORS View PostOk take the plane out of the equation. Just look at the wheels. If they roll forward at 5mph and the conveyor moves backwards at 5mph, how would they move? The question states that the conveyor EXACTLY matches the speed of the wheels. So as the wheels speed up the conveyor does as well. For the plane to travel forward it would need the have the wheels spin faster than the conveyor. According to the quest that’s not possible.
I’m thinking skate board on a tread mill. If you stand on one, the wheels are spinning at the speed set on the treadmill. You aren’t actually moving anywhere but the wheels are spinning forward as if you are. If you are pushed from behind you could move forward but that’s only because the treadmill is no longer “exactly matching the speed of the wheels”
Per the question if I was on a skateboard on a treadmill and someone pushed me from behind, the treadmill would speed up exactly matching the opposing force, therefore canceling it out.
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Originally posted by CabezaBlanca View PostIf someone pushed you from behind then you will move forward. I don't care how fast the tread mill moves and the wheels don't either.
Theoretically (according to the question), what if the speed at which you were pushed forward was exactly and instantaneously counter reacted by the treadmill?
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Originally posted by FLASH_OUTDOORS View PostOk take the plane out of the equation. Just look at the wheels. If they roll forward at 5mph and the conveyor moves backwards at 5mph, how would they move? The question states that the conveyor EXACTLY matches the speed of the wheels. So as the wheels speed up the conveyor does as well. For the plane to travel forward it would need the have the wheels spin faster than the conveyor. According to the quest that’s not possible.
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Originally posted by CabezaBlanca View PostThey pulled the belt, not the plane. It's the exact same scenario as the OP.
Originally posted by Walker View PostFrom the original question we don't even know if the engines are running.
Originally posted by Old Bald Guy View PostWrong, if the conveyor is running the same speed as the wheels and the wheels aren’t moving the conveyor won’t be moving either.
The car on the dyno is strapped down. Ever see what happens when one comes loose? Plus the car on the dyno is driven by the wheels the plane isn’t.
Originally posted by wickll View PostThink about a float plane..
It doesn't have ( or need) wheels to provide the thrust. The prop does that. All the wheels do is prevent friction from slowing it down. (or providing another force to overcome).
Well as much as I hate to admit it. I believe I’m wrong here. After watching the video on myth busters I understand differently.
The plane and the conveyor have no effect on each other BECAUSE OF THE WHEELS!
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Originally posted by Artos View PostWhat am I missing??
Pulling the belt causes the wing to catch air / lift with the forward momentum...a stationary spinning belt like a treadmill does not.
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