read what you just said..."it doesnt matter how fast its going while it is stationary"

it cant be stationary. if it is stationary, then technically the treadmill isnt moving either, because the treadmill tracks the plane's speed. so yes, it can move. stop thinking of it as the wheels drive the plane.

its stationary because the conveyeer belt is counteracting the force of the wheels. if the plane is going 500mph forward, and belt is going 500mph back it wont move. get on a tread mill and start running toward new york and tell me when u get there...assuming you're running the same speed as the treadmill spins u'll never move a foot eventho you'll be running 10mph.

tsar is right bout the new york then, cuz the tread mill is acting upon the legs which are driving u forward. the wheels do not drive the plane forward, they are rollers. get it yet?

I still say we just call myth busters and let then find out that the JET plane will not move.

Well, everyone can eat my ass now. This thread is now over.

http://videos.streetfire.net/player....D-D6BA1A43A06B

Watch it and weep


:)

what about EQUAL speeds? u know there's absolutely no chance that those were equal.

actually prolly tomorrow, or sat. ill take my treadmill a fan and a skateboard and do the same. but how do i post it here?

you can upload it to streetfire. just make sure its a strong enough fan to move the skateboard on even flat ground

oh, and notice it didnt gain speed after getting off the paper...stayed constant the whole time. and i think the speeds were pretty close to being the same...if i had a skateboard i'd do it too....but im straight so i dont

dont worry about the fan. i have a couple and one of them is pretty powerful if that needs to be used. I just have to figure out how to mount it on the skateboard :lol:

duct tape my friend..duct tape. im gonna see if i can find anything in my house that rolls freely and try it out as well

i just want to clarify somehting that i think a few people arent understanding..

When some of us say the plane will take off, we do not mean it will go from a dead stop all of a sudden to being airborne. that is impossible, we all agree you need speed to be able to achieve lift. what we mean is that it will eventually take off. It will begin to move forward and accelerate, and once the speed needed for lift is reached it will then take off. Additionaly, if the plane will be on the treadmill up until the time of liftoff, the treadmill MUST be as long as a normal runway, not just the length of the plane, if that was the case, the plane would roll forward and off of it. i just wanted to say that since i think people are thinking of it as IF the plane will lift off right in the same spot where it started from. which it wont, but like i said eventually it will though.

:stupid:

POST NUMBER 2500!!! :w00t:

Great find matt, that video proves its will take off. I love what the guy says at the very end. "suck it". :lol:

That doesn't prove anything!!!!!!! It's a fan on top of a skateboard of course it's gonna move as soon as the rearward force (moron with paper) stops acting on it. If the conveyor belt acting on the plane stopped, the plane would move forward but wouldn't be able to take off. They are two totally different things. Granted the plane would be able to take off much, MUCH sooner because it would take longer to acheive necissary lift (not speed) but still it couldn't take off on the runway.

look at the video again, the plane is clearly moving forward at the same time the guy is pulling the paper

~Ted

did you even watch the video?

the speed of both must be matched exactly, u cant do it with your hands.

who cares if the speed is matched- just by looking at that video, you could pull the paper EVEN faster than the skateboard is moving and it will still move forward.

~Ted

um...who cares? go re-read the problem problem it clearly states that the speed must be the same. and i doubt paper was moving faster, and if you think that if i put a piece of paper under a skateboard and yank it as hard as i can and it will still move forward you must me smoking funny cigs.

actually it probably will still move forward, as long as you pull straight back and not up + back

ooh this gives me an idea. anyone got that type of paper? we tape it to the bumper of someones car, start the fan going...and start the car going at idle speed. that should be able the same speed as the fan+skateboard, this way the speed will stay the same, or we can make it faster, and if we have a lot of the paper we can make it really long

it would be hard for me to yank straight back so im thinking it will hit the wall behind me. its ok ill try it with my treadmill if i need a faster one ill go to my friends house :lol:

damn i missed the second paragraph u typed...wouldnt the skateboard and the car be going in the same direction then?

ummm...not if you turn the skateboard/fan the opposite way? lol not sure what youre trying to say there

any treadmill should be fast enough for that fan/skateboard thing, it wasnt going very fast at all. walking speed

This argument would make sense if this experiment were being done in a wind tunnel, otherwise it does not. It is the force of the air acting upon the wings of the plane that causes it to fly. Without air actively moving over the wings it won't lift off. Typically the plane is moving across the ground at 100mph (using a number just for arguments sake, it's purely arbitrary), the air is not moving therefore when the plane moves it is going through the air, the air passing over the wings causes it to take off. You could do this inversely, the plane could be totally stationary and not moving but there would have to be a 100mph wind in order to get it to lift off. The plane could lift off the ground and fly not moving, not generating any thrust provided that the air was moving fast enough around it to generate lift. When you are moving the plane forward and at the same time counteracting that forward motion with rearward motion you are cancelling out any motion of the plane, and since the air will not be moving over the surface of the wing fast enough to create the sufficent amount of lift it will not take off. Another example: I'm sure everyone here has seen a car at high speed catch a little too much air underneath it and go airborne. It's creating lift under the car. Now take that same car and strap it on a dyno, or rollers or whatever you want. Take that car up to 180, 200mph, and then introduce air to the bottom of the car. Will it lift up off the dyno or the rollers? No because it is not moving FORWARD through the air, if the air was blown at the car at that 180 or 200mph wile it was stationary it would though. Seriously, i'm not just blowing smoke at you guys, i used to be really, REALLY into planes when i was younger.

well youre still not getting it though. the plane is going to be moving forward at a normal speed for takeoff, regardless of how fast the conveyor is moving underneath. we all understand how planes use lift to take off.

The motion would only be counteracted if the plane were driven by the wheels, this has been said numerous times, other people have realized its true, i dunno why some of you are still so stubborn. your car example does not work because the car is driven by the wheels.

what I'm saying is who cares for the simple reason that this video clearly shows it will work and based upon a lot of peoples thinking, if you moved the treadmill or pulled the paper faster than the plane was moving, that should ensure that your theory is correct and the plane/object will not move forward. So try it tomorrow with your treadmill, after you try to match speeds do another trial and let the treadmill move faster than the plane/object is moving and you should yield the same results as if the speeds were matched.

and as far as this " and if you think that if i put a piece of paper under a skateboard and yank it as hard as i can and it will still move forward you must me smoking funny cigs" If its just a skateboard and no source of power, of course the skateboard will not move forward, but that is not what this "debate" is about nor the experiment in the video. We're testing it based on the thrust of the plane/object, not an object sitting still with no momentum.

~Ted