NY and Rinky -
Quote:
Where are you coming from with the 'There is no force between the belt and the plane'. Did we suddenly hack the wheels off and remove Gravity or something?
Essentially, yes. The rolling resitance would be measurable, but that friction force will not translate to enough of a force to overcome the thrust.

So, you could treat this problem as if the wheels did not exist. A free-body diagram would show the force of gravity acting down, the force of friction acting back, the force of thrust acting forward and (given enough air speed) the force of lift acting up. The biggest forces win. Thrust will be bigger than friction, therefore it wins and the plane moves forward (again, regardless of what is happening below it). At some point lift becomes a bigger force than gravity, it wins and the plane takes off.

The only way the belt could prevent the plane from taking off is if the plane's brakes are on. Then the full force of the belt would be translated to the plane, instead of only a very small fraction of that force being translated through friction.

NY and Rinky, you have to disconnect the ground from the plane, in this problem it does not matter.

Edited to bold the part above, because that is the central arguement.