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Unread 22-05-2012, 13:44
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Re: The physics of pushing

Quote:
Originally Posted by DonRotolo View Post
OK, maybe this will help:

If each wheel gets 20 ft-lbs of torque, and the wheel is 6" in diameter, the force acting on the carpet* is 20 / 0.25 = 80 Lbf. (20 is the torque in ft-lbs, 0.25 is the radius of the wheel in ft, and Lbf is "pounds force" (different from pounds weight)).

*Theoretically. Remove maybe 5% for losses (as suggested above), you get 76 Lbf.

Four wheels, 76 * 4 = 304 pounds of force.

Assumes you don't break traction with the carpet.
Bardd: note that this would require a wheel tread with a coefficient of friction of around 2.0, much higher that commonly used tread materials. When you finish your calculation you should double-check it with other potentially limiting factors such as traction and component strength.
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