Brainteaser Options

[james]

Here's a question for you:

"A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?"

A couple of links discussing it (and some funny rationalizations for peoples incorrect assumptions):
www.kottke.org/06/02/plane-conveyor-belt
www.straightdope.com/columns/060203.html

[Emily]

can we leave out that plane taking off, we all know it wont take off unless it moves, all we need to work out if how its gonna get up to speed. If your little matchbox car has got a jet engine and is on a mini conveyer that can move as fast as it little wheels then unless there is another force to counteract the weight of the car keeping it on the wheels then the conveyer will keep going faster and faster still doesn't work!

The thing i don't understand is why the wheels end up going faster then the conveyer, because that is what you are saying is it not?

the difference to a plane and a car is that the motion created by the wheels is moving the car, where as the wheels on a plane just let it move, but it would still be the same in the end i reckon

ding! lights come on, sorry i am wrong!

This post has been edited by Emily: Feb 24 2006, 03:48 PM