Quote:
Originally posted by Mobycat:
Interestingly enough, my brother is a civil engineer (with about the 20 years experience).

His take was that there would be no wind over the wings. BUT...he also made it a point to say it's a trick question.

Edit to add - if the plane is going 20 mph, does the conveyor think it's going 20mph to the ground or to itself?

If the conveyor thinks it's to itself, shouldn't it be impossible for the conveyor belt to match it? That is, if the conveyor think's the plane is going 20 mph to the conveyor belt, the conveyor belt goes to 20mph...but then the plane is going 40 mph to the belt - and so on and so on?

Which brings back the question - what's the speed in relation to?

If it's to the ground away from the plane - then the plane should take off. If it's to the ground underneath - the conveyor - it's an impossible scenario.
Speed isn't revolutions per second, which is what any measurement of the tires would give you. That's "angular speed", and not "speed". In a car, angular speed is translated into speed by the speedo, gears, and in newer ones, electronics. But the angular speed of the tires and the speed of the vehicle are never coinciding.

Moby, run my explanation by your brother and see what he has to say. Don't paraphrase; copy that last post directly and ask him about it. I'm betting a little light-bulb will go off over his head (maybe even a good palm-smacking of the forehead if he's that kinda' person) and he'll tell you the plane takes off...