The work done by the pushing force is equal to the change in the cart's potential energy. The potential energy of the cart is equal to its mass multiplied by the acceleration due to gravity and the height of the platform.
Work = (200 kg)(9.8 m/s2)(1.5 m) = 2940 J
The work done against friction is equal to the force of friction multiplied by the distance along the incline.
Work against friction = (150 N)(7 m) = 1050 J
Therefore, the total work done by the pushing force is equal to 2940 J - 1050 J = 1890 J.
A 200-kg cart is pushed slowly up an incline. How much work does the pushing force do in moving the cart up to a platform 1.5 m above the starting point if friction is negligible?
(Use above problem) If the distance along the incline to the platform is 7 m and a friction force of 150 N opposes the motion.
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