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#292
11-23-2005, 04:36 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
[ QUOTE ] Patrick, you understand that if the conveyor is going 293476943769437694376mph then the plane has to go 293476943769437694376 + 1 mph to move forward? [/ QUOTE ] The plane doesn't - the wheels' tangential velocity does, but that has absolutely no effect on the forward motion of the plane - the bearings are frictionless - no force gets through to the plane itself. [/ QUOTE ] Finally we admit that the wheels must be going faster than the conveyor, hence the OP conditions are NOT satisfied. 
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#293
11-23-2005, 04:36 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
[ QUOTE ] [ QUOTE ] [ QUOTE ] thats the whole point of a treadmill, so you can run WITHOUT MOVING. [/ QUOTE ] Now throw rollerskates on and use the handles to pull yourself forward. [/ QUOTE ] I'm going to expand on this a little. Imagine you're on the treadmill, on roller skates with perfect bearings. Someone is controlling the speed of the treadmill for you, and they keep turning it up. Since you're on frictionless wheels, the speed of the treadmill doesn't affect you, right? Okay, grab hold of the handles now. Imagine that the dude keeps cranking up the speed on the treadmill. Is there any speed he could possibly turn it up to that could stop you from simply pulling yourself forward with the handles if you wanted to? [/ QUOTE ] people are going to say "but when you pull yourself forward, the wheels will be going faster than the treadmill" which is partially true imagine instead of regular rollerblades with normal wheels, your POS rollerblades have cog wheels and the treadmill has, well, treads, so that when you pull yourself forward you are forcing the treadmill to speed up (while matching the velocity of your wheels) lift off!!! [/ QUOTE ] Hello paradox. If you move relative to the treadmill, your wheels must cover more ground then the treadmill in the same amount of time, if you are moving relative to the treadmill the rotational speed of your wheels cannot, by definition, be the same as the speed of the treadmill.
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#294
11-23-2005, 04:37 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
i am the engineering type in every possible sense of the word [/ QUOTE ] You drive a train for a living?
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#295
11-23-2005, 04:37 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
[ QUOTE ] [ QUOTE ] Patrick, you understand that if the conveyor is going 293476943769437694376mph then the plane has to go 293476943769437694376 + 1 mph to move forward? [/ QUOTE ] The plane doesn't - the wheels' tangential velocity does, but that has absolutely no effect on the forward motion of the plane - the bearings are frictionless - no force gets through to the plane itself. [/ QUOTE ] Finally we admit that the wheels must be going faster than the conveyor, hence the OP conditions are NOT satisfied. [/ QUOTE ] sure they are - the conveyor velocity simply accelerates instantaneously with the wheel's tangential velocity. but as Patrick said, these accelerations have absolutely nothing to do with the forward acceleration of the plane.
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#296
11-23-2005, 04:38 PM
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Re: think about this...
[ QUOTE ]
 [/ QUOTE ] wow
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#297
11-23-2005, 04:39 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
[ QUOTE ] [ QUOTE ] How can a CPA understand this (thanks to Patrick [img]/images/graemlins/smile.gif[/img] ) and engineering types can't [img]/images/graemlins/confused.gif[/img] [/ QUOTE ] to be fair, these guys really aren't "engineering types" i think the "physics types" have an edge over the "engineering types", although patrick is sort of both. [/ QUOTE ] the physics types assume the bearings are frictionless, whereas the engineering types live in the real world and account for these types of things [img]/images/graemlins/tongue.gif[/img] [/ QUOTE ] You can't back your way out of this one. Quit trying to pretend like you can't imagine frictionless bearings when you've already accepted a runway flying by at 29674967497694376mph. You were completely wrong and it wasn't because you didn't accept perfect bearings. The only difference non-perfect bearings makes is that the engines would have to be strong enough to overcome whatever insiginificantly small effect the bearing friction would have. You could mount an engine on there that's strong enough to take off if you had the brakes on fully, let alone a little bit of bearing friction.
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#298
11-23-2005, 04:39 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
[ QUOTE ] i am the engineering type in every possible sense of the word [/ QUOTE ] You drive a train for a living? [/ QUOTE ] high on cocaine.
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#299
11-23-2005, 04:39 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
[ QUOTE ] people are going to say "but when you pull yourself forward, the wheels will be going faster than the treadmill" which is partially true imagine instead of regular rollerblades with normal wheels, your POS rollerblades have cog wheels and the treadmill has, well, treads, so that when you pull yourself forward you are forcing the treadmill to speed up (while matching the velocity of your wheels) lift off!!! [/ QUOTE ] Hello paradox. If you move relative to the treadmill, your wheels must cover more ground then the treadmill in the same amount of time, if you are moving relative to the treadmill the rotational speed of your wheels cannot, by definition, be the same as the speed of the treadmill. [/ QUOTE ] we are moving relative to the entire machine, we are not moving relative to the belt thingy
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#300
11-23-2005, 04:40 PM
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Re: Physics graduate from Daryn\'s alma mater\'s answer
[ QUOTE ]
[ QUOTE ] [ QUOTE ] Patrick, you understand that if the conveyor is going 293476943769437694376mph then the plane has to go 293476943769437694376 + 1 mph to move forward? [/ QUOTE ] The plane doesn't - the wheels' tangential velocity does, but that has absolutely no effect on the forward motion of the plane - the bearings are frictionless - no force gets through to the plane itself. [/ QUOTE ] Finally we admit that the wheels must be going faster than the conveyor, hence the OP conditions are NOT satisfied. [/ QUOTE ] Amen, and good night.
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