Plane On A Conveyor Belt

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Will The Plane Fly?

  • Hell Yeah - That Plane WILL Fly!

    Votes: 0 0.0%
  • Um .. No, The Plane WILL NOT FLy.

    Votes: 1 50.0%
  • That Plane is Going To Crash.

    Votes: 1 50.0%
  • Screw The Plane! Bring on the EB.com Art Gallery!!!

    Votes: 0 0.0%

  • Total voters
    2
Thanks. I must admit I thought at first it wouldn't fly either and had to convince myself otherwise.

I've thouroughly enjoyed this riddle. It's deceptively simple and surprisingly hard to explain in a straightforward way.

Problem is, what do we argue about now that the last holdout is convinced?

 
if you want, I could pretend otherwise :rolleyes:

the external force arguement was the clincher for me.

 
Thanks. I must admit I thought at first it wouldn't fly either and had to convince myself otherwise.
I was too until someone pointed out the wheels were just there to support the planeand minimize friction, noit apply tractive force. Then the light came on and I felt a huge "DUH!" moment.

 
Ok - At risk of being banned from the site, I'm just going to say I still don't see how the plane will move, let alone take off. The way I understand the question the conveyor belt moves in the opposite direction at the same speed the plane moves forward. So relative to anyone standing on the ground, the plane doesn't move. The thrust from the engines can be as big as you want but if there's no wind over the wings it's going to sit there.

well, we'll see...

 
Ok - At risk of being banned from the site, I'm just going to say I still don't see how the plane will move, let alone take off. The way I understand the question the conveyor belt moves in the opposite direction at the same speed the plane moves forward. So relative to anyone standing on the ground, the plane doesn't move. The thrust from the engines can be as big as you want but if there's no wind over the wings it's going to sit there.
well, we'll see...
The engines force acts on the air (not the ground or conveyor belt), there fore the conveyor belt can move at any speed it wants to, it just causes the (free rotating) wheels to spin faster as the plane moves forward.

Now if you put a giant vacuum behind the engines that sucked the same volumetric flowrate that the engines put out... that would keep the plane from flying

 
willing to bet thrust beats tire friction...
That would be interesting... I'd get on a jet, but not a prop. That's a lot of skidding down the runway. I wonder how hard it would be to keep it going straight - probably no worse than a strong cross-wind.

 
Please delete me from this reply all email.

Everybody #&$^ing knows the #&$^#  plane WILL NOT FLY!

(but only because it's an infinity paradox: if the wheels move at the same speed as the conveyor, both will instanstly reach infinite speed and the bearings will explode. BOOM, solved it!)

 
This question is old news.  It's time to update the question.  Let's say there's a treadmill mounted on an airplane. If the airplane is flying at 1 mph slower than the speed of sound, but you are running on the treadmill at a speed of 6 mph, will your body be harmed when it breaks the sound barrier?

 
Wait, is the treadmill INSIDE the airplane or outside?

And what color is the airplane?  Need to define these seemingly insignificant details first.

 
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