Because it won't stay in one spot...?Originally Posted by Hektik
Because it won't stay in one spot...?
AIM: RuinerTT
2005 Nissan Pathfinder LE
Different logic. Your legs power you and are directly connected to the moving sidewalk. The wheels on an airplane have NO power and roll freely. The engines that "pull/push" through the air provide the power on the plane.
AIM: RuinerTT
2005 Nissan Pathfinder LE
$10? Don't be a pussy...stick by your guns. It's easy money for you if you know 100% for sure...o and no
AIM: RuinerTT
2005 Nissan Pathfinder LE
ok so occording to his logic, if i was on roller blades and being pulled by a rope attached to a deisel truck, and tried to go the other way i wouldnt move.
Ughhh... this is a confusing ass thing... I think that if it was like a jet plane, ya it would be able to take off... it'd be the equilvenent of a RPG... all they have is thrust, no lift or movement to get them started up in the air. But then I sit here and try and imagine an old prop plane taking off without REALLY moving anywhere.... and I just can't picture it.. I mean ya, they engine would be up to speed but I dont see how it would be able to get down the runway with a treadmill moving the opposite direction... I mean, free spinning wheels would be basically the equivelent of just holding the plane in place wouldn't it? eh... fuck it, I dont understand this stuff... i'll leave it to the big boys before my head explodes...
No, the wheels are free-spinning. What FORCE could they really apply backwards?
AIM: RuinerTT
2005 Nissan Pathfinder LE
you know what I will go ahead and admit defeat. you wanted a discussion and you got one. but now I see what you mean.
Look at it this way:
If you have a plane on a frozen sheet of slippery ice...and the plane's wheels are locked (the brakes are on). Will the plane take off under throttle?
AIM: RuinerTT
2005 Nissan Pathfinder LE
no what ruiner is explaining is that the wheels will spin at 100knots and the treadmill will spin at 100knots BUT the jet will go forward and the treadmill will go backwards but since the wheels are free spinning they will spin backwards with the treadmill and the jet will still go forward so even though the wheels are spinning the jet will still move forward. the treadmill would have to be as long as a regular track just so the jet has enough distance to pick up speed but the wheels will just spin regarless
yea I get what ur saying nowLook at it this way:
If you have a plane on a frozen sheet of slippery ice...and the plane's wheels are locked (the brakes are on). Will the plane take off under throttle?
BINGO! Actually,the wheels would spin at 2x the rate of the forward movement...no what ruiner is explaining is that the wheels will spin at 100knots and the treadmill will spin at 100knots BUT the jet will go forward and the treadmill will go backwards but since the wheels are free spinning they will spin backwards with the treadmill and the jet will still go forward so even though the wheels are spinning the jet will still move forward. the treadmill would have to be as long as a regular track just so the jet has enough distance to pick up speed but the wheels will just spin regarless
AIM: RuinerTT
2005 Nissan Pathfinder LE
got it nice diagram toBINGO! Actually,the wheels would spin at 2x the rate of the forward movement...
if u hold a shopping on a cart on a treadmill, the wheels of the cart will be going say 10mph while the treadmill goes -10mph. the cart however, does not move. if u accelerate the treadmill to -20mph, the wheels of the cart will spin at 20mph but the cart will still not move. therefore it doesnt matter what speed the treadmill goes because the wheels are free spinning. so now that u have a cart not moving, but rolling along with the treadmill, put jet engines on it. will the cart move forward? get it?
You made a wise choice.yea I get what ur saying now
AIM: RuinerTT
2005 Nissan Pathfinder LE
I lied I gambled once in my life it was a quarter (25c) in a casino lost them will never do it againYou made a wise choice.
I dont see them applying any force, but I just can't see them moving forward, rather just spinning in place since the plane is pulling them one direction, and the treadmill is pulling them in the opposite at the same speed. like i said, i'm just gonna leave this to you guys... never claimed i was smart when it comes to these type of things lol... i'm much more a visual/hands on person than i am able to do crap in my head lol...
I'm late and I like your explanation. Your Idea of freely spinning wheels is true, but remeber, there are power to the treadmill. So it's like an opposite upside down situation.
So it's like how your car is being dyno or when you do the OBDI Emission check. The Plane will be the rollers of the machine (don't know what's it called) and the Treadmill is the car itself.
However, your "real life" experience has nothing to do with the plane on the treadmill since
A. The paper doesn't work the same way as the tread mill. Treadmill puts out torque and power.
B. Plane requires horizontal air movement to lift it up.
Since:
1. PLane has +A velocity on +X Direction
2. Treadmill has -A Velocity on -X direction.
According to Physic,
If there's equal and opposite force that applied at the same time, there won't be any changes in the X direction movement.
Therefore, there won't be any -A^n velocity of the air movement.
The plane will not take off.
ok reading through this entire thing and hearing mostly ruiner and hektik debate, i'll have to say that my first instinct was to say the plane won't take off. while i understand that the wheels are free spinning, i still believe that the jet engines are what causes the wheels to spin at any speed (which is then matched by the treadmill), therefore causing the plane to stay in the same place.
however, after reading through ruiner's further explanation, i came to think that maybe he is right. yet the only way i'd agree with that is if somehow, the wheel speed does not match the treadmill speed. by that i mean the jet engines can propel it enough to where the wheels will outspin the treadmill, thereby giving it forward movement and lift and all that. but then again, this doesn't really agree with ruiner's original supposition.
after reading interlude's post just now, i'm back to thinking that this plane will not take off......either way though, thanks for making me think like this, it's been a while
If you are so sure, then take a bet with me.
I will say this: you are wrong.
It IS NOT like your car on a dyno. In a car, the power goes to the wheels. In a plane, it "pushes" through the air via the engines. There is NO connection with the ground. BIG difference. Answer me this: how does a plane with sleds on the bottom take off in the snow? No wheels...
The plane, no matter how fast the treadmill is spinning, will push forward, THROUGH the air, and down the treadmill (that is as long as a runway). During that time, the plane will pick up speed and finally reach take off velocity.
If you don't believe me, bet me.
Last edited by Ruiner; 05-25-2006 at 09:46 AM.
AIM: RuinerTT
2005 Nissan Pathfinder LE
If you don't believe that it will take off, then bet me. Put up or shut up.after reading interlude's post just now, i'm back to thinking that this plane will not take off......either way though, thanks for making me think like this, it's been a while
AIM: RuinerTT
2005 Nissan Pathfinder LE
Apparently nobody else gets it, though. That worries me, honestly. It's a VERY simple concept. The treadmill is only there to cause confusion, but that's it. The plane will still take off (given a long enough treadmill).
AIM: RuinerTT
2005 Nissan Pathfinder LE
i do believe you, IF you can concur that in order for the plane to actually move forward on the treadmill and take off, it's wheels will have to spin at a faster speed than the treadmill. because although i agree there is no power going directly to the wheels (therefore making it different than a car, or a person running), the plane is still "grounded" via the wheels, and needs the wheels in order for traction and to pick up speed with.If you are so sure, then take a bet with me.
I will say this: you are wrong.
It IS NOT like your car on a dyno. In a car, the power goes to the wheels. In a plane, it "pushes" through the air. BIG difference.
The plane, no matter how fast the treadmill is spinning, will push forward, THROUGH the air, and down the treadmill (that is as long as a runway). During that time, the plane will pick up speed and finally reach take off velocity.
If you don't believe me, bet me.
Traction? No
Let me ask you this:
A plane is sitting on a huge frozen lake bed. The frozen sheet is slippery. The plane locks its wheels (puts the brakes on) and then applies engine thrust. Will the plane take off?
AIM: RuinerTT
2005 Nissan Pathfinder LE
i believe traction is present and valid considering it's on a treadmill, however, i see your point that it can be arbitrary. however, what i seem to have trouble conceiving is how the plane will actually MOVE DOWN this treadmill when the treadmill is moving against it at whatever speed the wheels are spinningand yes, that plane on the frozen lake will take off (only if you have iceman from top gun flying it though
Take the treadmill out of the equation. Suspend the plane from cables(plane not touching the ground) and fire up the engines. Once the plane has enough thust it will move forward. The wheels merely reduce friction between the ground. At some point the plane's engine overcomes the weight of the plane itself and moves forward.
i believe traction is present and valid considering it's on a treadmill, however, i see your point that it can be arbitrary. however, what i seem to have trouble conceiving is how the plane will actually MOVE DOWN this treadmill when the treadmill is moving against it at whatever speed the wheels are spinning
Think about it this way:
- Stand on a treadmill with roller skates....
- Hold onto the bar and keep yourself stationary.
- At this point, your wheels and ONLY your wheels are spinning at the speed of the treadmill. You are stationary.
- Now, try to pull yourself forward. It should be VERY easy to do. Increase the treadmill speed. Still easy to pull yourself forward.
- Now, imagine that you strapped a jetpack on your back and used those engines to "push" you forward while still on the treadmill.
- The jetpack = a plane's engines
It's VERY simple... you will move forward and increase speed much like a plane will move forward, increase speed after enough distance, and finally take off.
AIM: RuinerTT
2005 Nissan Pathfinder LE
exactly, i understand/comprehend that perfectly. i guess what i am really curious about, and something that originally put doubt into my head (as well as countless others who have thought about this), is that when the thrust from the engines starts to push the plane forward, what exactly are the wheels doing? as in, what is the speed of the wheels? (even though i realize this is arbitrary!)
The wheels are spinning and nothing else! That is the fun of it. The wheels ONLY spin, freely! Actually, the wheels will spin at twice the rate of forward motion of the plane as the treadmill is doing the same speed in reverse.
So, the plane is moving at 100knots forward and the treadmill is doing 100knots in reverse...the wheels are spinning (and ONLY SPINNING) at 200knots. They still have no affect on the plane's forward motion. All the treadmill does is spin the wheels.
AIM: RuinerTT
2005 Nissan Pathfinder LE
perfect! that was my thinking originally, that in order for the plane to MOVE FORWARD, the RATE at which the wheels were spinning could not equal the rate of the treadmill moving against it (and speed of the treadmill and the wheels really have no bearing on whether or not the plane will take off). see? i'm with ya, just had to make sure i was understanding all parts of this "situation"The wheels are spinning and nothing else! That is the fun of it. The wheels ONLY spin, freely! Actually, the wheels will spin at twice the rate of forward motion of the plane as the treadmill is doing the same speed in reverse.
So, the plane is moving at 100knots forward and the treadmill is doing 100knots in reverse...the wheels are spinning (and ONLY SPINNING) at 200knots. They still have no affect on the plane's forward motion. All the treadmill does is spin the wheels.
hehe what happens when a wheel bearing locks up? :P I do completely understand though. as long as the jet engines are able to put force on something that isn't counteracting them, the plane will move. there is forward thrust regardless.
Who knows?
Your logic is still off. It has NOTHING to do with how fast the wheels are spinning, NOTHING. As I said earlier, a plane could take off with NO wheels on the snow or no wheels in the water or locked wheels on a sheet of ice.perfect! that was my thinking originally, that in order for the plane to MOVE FORWARD, the RATE at which the wheels were spinning could not equal the rate of the treadmill moving against it (and speed of the treadmill and the wheels really have no bearing on whether or not the plane will take off). see? i'm with ya, just had to make sure i was understanding all parts of this "situation"
The plane has to overcome the friction produced by the wheels. Since the wheels are free spinning, then the only friction that they are producing comes from the bearings... that's it. Once it overcomes that little bit of friction, the plane moves forward.
AIM: RuinerTT
2005 Nissan Pathfinder LE
the plane can't fly. it's been proven. since the plane is no moving there is no drag thus no lift.
hell, if it was possible the Navy would have giant floating treadmill.
i think maybe you're misunderstanding me or i didn't explain myself well enough? i understand the speed of the wheels have nothing to do with this equation, it's all about the force that's being applied by the engines. however, and please tell me if this is where i'm wrong, i believe the wheels must spin at a higher rate than the treadmill moving against it AS A BYPRODUCT of the force being applied to move the plane forward. because if this is not the case, then why is it that the wheels would freely spin at twice the rate of the treadmill? hope this clears it up for good
What would stop the plane from moving if it applied thrust from its engines?the plane can't fly. it's been proven. since the plane is no moving there is no drag thus no lift.
hell, if it was possible the Navy would have giant floating treadmill.
AIM: RuinerTT
2005 Nissan Pathfinder LE
Look at it this way: if the plane was in the air and YOU were making the wheels on the plane spin, would the plane fall out of the air? That's all that the treadmill is doing...spinning the wheels. NOTHING MORE.i think maybe you're misunderstanding me or i didn't explain myself well enough? i understand the speed of the wheels have nothing to do with this equation, it's all about the force that's being applied by the engines. however, and please tell me if this is where i'm wrong, i believe the wheels must spin at a higher rate than the treadmill moving against it AS A BYPRODUCT of the force being applied to move the plane forward. because if this is not the case, then why is it that the wheels would freely spin at twice the rate of the treadmill? hope this clears it up for good
Look at the diagram again and you will understand why the wheels spin at the plane's forward speed + the treadmill's speed:
AIM: RuinerTT
2005 Nissan Pathfinder LE
BET ME! Please, be a man and bet me if it is such a sure thing.the plane can't fly. it's been proven. since the plane is no moving there is no drag thus no lift.
hell, if it was possible the Navy would have giant floating treadmill.
AIM: RuinerTT
2005 Nissan Pathfinder LE
can't see the pic cuz it's being blocked by websenseLook at it this way: if the plane was in the air and YOU were making the wheels on the plane spin, would the plane fall out of the air? That's all that the treadmill is doing...spinning the wheels. NOTHING MORE.
Look at the diagram again and you will understand why the wheels spin at the plane's forward speed + the treadmill's speed:
but i understand what you're saying and even though i don't think i'm expressing it correctly, what i'm saying is what you're saying
and to hopefully prove that i do fully comprehend, here's a simple followup question that you can easily answer: would it be possible to have/build a treadmill that will move/accelerate in a manner in which it will actually keep the plane in the same spot and grounded?
lirl, all about betting today huh? i understand though with that new place you're getting, mortgages are a bitch
1. I said that plane = dyno roller, treadmill = car. Please reread what i said.If you are so sure, then take a bet with me.
I will say this: you are wrong.
It IS NOT like your car on a dyno. In a car, the power goes to the wheels. In a plane, it "pushes" through the air via the engines. There is NO connection with the ground. BIG difference. Answer me this: how does a plane with sleds on the bottom take off in the snow? No wheels...
The plane, no matter how fast the treadmill is spinning, will push forward, THROUGH the air, and down the treadmill (that is as long as a runway). During that time, the plane will pick up speed and finally reach take off velocity.
If you don't believe me, bet me.
2. Plane will take off on snow since there AREN'T any -A Velocity on X axis with -hp & -tq. Also, the snow surface is STATIONARY has enough friction for the plane to grip on. Treadmill has -A Velocity on X axis with -hp & -tq. It counters every +A velocity in the +X direction.
3. Plane doesn't require right velocity/speed to lift off, it requires enough lift force of the air movement. It relies on its speed to help it move ALONG the density of the air to cause enough lift. If the plan is to run on the space runway where there aren't any air, it will not have any vertical movement. It will move VERY fast on the outerspace runway, but not UP unless it has a thrust engine to push it up and changes its Y directional velocity. The plane can run at 500mph on the runway while the air is moving at the SAME velocity and SAME force and SAME direction as the plane, it still WILL NOT take off.
I don't believe it bet.But I understand your concept very well.
It's time for the Mythbuster to prove this.
Also, the PLANE WILL TAKE OFF on the treadmill if it has this condition:
A thrust engine that creates +B velocity in +Y direction.
If its thrust engine only has purely +A Velocity in +X Direction, it WILL NOT take off.
As long as the wheels are free rolling (neutral), no, not really. There is a small amount of friction in the wheel bearings. If the plane's thrust matches that friction, exactly, then the plane will stay stationary. Once the plane's thrust passes that friction amount, the plane will move forward.can't see the pic cuz it's being blocked by websense
and to hopefully prove that i do fully comprehend, here's a simple followup question that you can easily answer: would it be possible to have/build a treadmill that will move/accelerate in a manner in which it will actually keep the plane in the same spot and grounded?
AIM: RuinerTT
2005 Nissan Pathfinder LE
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