I am designing a transmission for my class but i have a couple of concepts i kinda confused, i have a 550lbs load, and i want to move 35mph=15.64m/s at a constant speed, assuming the drag coefficient to be Cd=.55 and the coefficient of rolling resistance to be Crr=.3 (tires on sand), i found out the two frictional forces going against a rigid body(my off road car) which are the sum of the Rolling resistance force and the force of aerodynamic drag which turned our to be F=815.21 N, i want to like to learn how to find the torque necessary to move it and the power required, do we keep power constant?, and does the power depend on torque or vice versa? Thanks in advance(adsbygoogle = window.adsbygoogle || []).push({});

here are the eqn used

http://upload.wikimedia.org/math/2/8/5/28560fb9ccae7b5f811de11f965d5478.png

http://upload.wikimedia.org/math/9/a/b/9ab71e6e4f97b6a9d63cfa5aded81f1a.png

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# Help design torque, power needed

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