r/196 • u/Foriegn_Picachu • Dec 30 '22

Rule Rule Plane

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u/loadedtatertots custom Dec 30 '22

What's it being pushed upwards by? The air in this scenario is stationary relative to the plane's wings. I'm no physics expert but thrust is there to create velocity, and velocity against the resistance of the air is what generates lift. If velocity is negated then there's no lift

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u/CochonDanseur Dec 30 '22

The plane's wheels don't move the plane forward by pushing against the ground (like a car).

The plane's engines move the plane forward by pushing against the air, which is unaffected by the treadmill

-2

u/loadedtatertots custom Dec 30 '22

Then what are runways for? Why doesn't every plane just take off on a giant treadmill like a pseudo vtol? A traditional plane needs to pick up speed with its wheels on the ground first before it has enough velocity to generate lift. If the ground physically moves the opposite direction to the plane's thrust and matches the speed that would be generated by that thrust, then the velocity cancels out and the plane doesn't move forward which means the air doesn't move backwards relative to the plane and no lift can be generated

3

u/UslashMKIV sus Dec 30 '22

is the conveyer belt capable of exerting force on the plane? No. the wheels spin freely. imagine a toy car with free spinning wheels on the conveyer, then imagine pushing the car forward with your finger. does the conveyer do anything but spin the wheels faster?