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Old 07-02-2021, 05:06 PM   #92 (permalink)
Vman455
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Quote:
Originally Posted by aerohead View Post
1) since there were no arrows provided in the illustration, I did a napkin sketch.
2) the car is moving from left to right.
3) the wheels in ground contact are rotating clockwise.
4) the upper wheels are powered by their contact with the reduced-radius axle of the ground contact wheels.
5) as the lower wheels rotate clockwise, as in meshed gears, the upper wheel spins counterclockwise.
6) a plank, resting on the upper wheels will be pushed off the cart, falling behind it.
That, or the Kool-Aid's been real good!
You're half right. The plank will move backward relative to the car and slide off the back. But it will also move forward relative to the ground, at a velocity less than that of the car. No Kool-Aid required.
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