Quote:
Instead, here’s a quick test to determine whether you should read this chapter.
If you’ve been on the internet in the past ten years, I’m sure you’ve heard this
riddle. There’s a plane on a magical threadmill runway. The threadmill defies
the laws of physics and can rotate as fast as the plane’s wheels while going
in the opposite direction. If the plane rolls forward at 10 mph, the runway
underneath rolls backwards at 10 mph. The plane’s wheels spin up to 200 mph
and the runway rolls back at 200 mph. The question is, will the plane move
forward and take off or remain stationary?
If you had to think about it for even a second, you need to read this chapter.
The answer of course is yes, the plane will take off as normal.
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The reason it is so confusing is because they don't talk about the plane creating thrust. They only state that the wheels are spinning at 200mph and the 'magic' conveyor is moving in reverse at 200mph. In that sense the plane would stand still.
So they are INCORRECT. As far as I can tell.
If the wheels are spinning 400mph forward and the conveyor is moving in reverse at 200mph then the plane is moving forward at 200mph.
See the discrepancy?
The only way they can make the wheels and the conveyor spin at the same rate, while creating lift, would be if the entire conveyor system was maintaining lateral position with the plane.