so gliders have engines, too? never knew that.Originally Posted by speedminded
so gliders have engines, too? never knew that.
No but gliders are towed into the air by a plane with a engine.so gliders have engines, too? never knew that.
then there would also have to be a tow-plane on the treadmill with the glider. the problem only says there's one plane.
you guys are completely missing the point here... even if the plane could move and keep up enough speed for flight, there is no air passing under the wings. Therefore: no lift. The damn plane could stay there allllllll day long, but never get airborne.
without moving air to create drag against the wings, there can be no flight.
what's so fucking hard to understand about that?
(It would probably work if there was a fan in front of the conveyer belt pushing against the plane.)
What prevents the plane from moving forward? Think about it!
Here's another analogy, on a skateboard and approaching a normal everyday treadmill that is on, you're rolling towards its then lean back shifting your weight behind the rear wheels lifting the front of the skateboard just before coming in contact with the treadmill....now the rear wheels are on the ground and the front two are on the treadmill. Are you going to fly backwards or just sit there spinning the front wheels?
You will be spinning the front wheels and sitting on your ass. But what does this have to do with anything?? Your weight is still shifted to solid, non-moving ground. Sit your entire fat ass on all four wheels on a moving treadmill and you WILL fly backwards with skateboard and all.
I got free clear tails with my ride.....
in the problem, it states that the plane is moving one way while the belt is moving the opposite way at the same exact speed. Think about it. (-)10 + (+)10 = ZERO. the two speeds cancel each other out and the plane goes nowhere.
What you just admitted to is that the wheels spinning means nothing - which is what we want you to see. So, you got your -10 and you +10 - PERFECT!! Plane is going nowhere fast. Now fire up the JET engines to 100% - the plane moves forward yes? And if not - what is stopping it from moving forward.
"I'm not a gynecologist... but I'll take a look."
Yes, but you are not applying 100% of anything to the treadmill. The treadmill in the original question, is asked to match the speed / force / thrust of the plane.
It's simple.. if you can accept that -10 and + 10 = Zero than you'd have to accept that the thusters were set so that the plane is at +10 (10MPH forward) and the threadmill is moving at -10 (10 MPH Backwards), so the plane is stationary, (AT ZERO), wheels spinning and all, UNTIL you fire the engine at 100%. This is logical. Cause if the treadmill is at -10 and the plane's engines are off, then the plane will move backwards on the treadmill at -10 (10mph backwards), just like if you were to just stand still on a moving treadmill. Even with rollerblades. Correct so far?
If you accept the principle that this magical threadmill is able to keep the plane stationary at -10/+10 then you'd have to accept the principle, that if all the stars align, and the treadmill is magical enough to instantaneously match ANY motion, thrust / speed of this plane, that it theoretically be possible to hold the plane stationary AT ANY SPEED, UNTIL the thursters are able to overcome this opposite force/resistance/etc. to start moving forward and lift off (eventually)
Last edited by ISAtlanta300; 08-16-2007 at 03:42 PM.
I got free clear tails with my ride.....
Why would you be sitting on your ass? Can you not stand motionless with the front of the skateboard up in the air? If you did that up against the treadmill with two wheels on the ground and two on the treadmill whats going to happen? It's just going to spin the front wheels backwards the same speed at the treadmill right but you're not going to go anywhere right?
It has EVERYTHING to do with it. You are right, if you sit your ass on the skateboard you will go backwards if the treadmill is on, BUT what happens if you hold on to the bar or someone behind you places their hand on your back...you don't go anywhere right? You holding or their hand is no differant than the thrust of a plane engine. You can speed the treadmill up all the way and it will won't take any more effort to hold you in the exact same spot, why? Because the wheels are free spinning.
This thread from the very beginning, starting with the title, pertains to planes. Planes propel themselves, planes use runways, gliders use neither.so gliders have engines, too? never knew that.
Why are you lauging, that vid proves you're wrong
repped.
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