Q- Gopal finds that a force *F* is required to push a crate of mass *m* up a plank of length *L* into a truck whose platforms is a vertical distance *h* above the road.

(a) How much work does Gopal do in pushing the crate up the plank?

(b) Calculate Gopal’s work input if the crate has a mass of 100 kg, the length of the plank is 5.0 m, the applied force is 490 N, and the platform is 1.2 m above the road.

(c) What is the increase of potential energy of the crate once on the platform?

(d) How much work did Gopal do in overcoming friction?

(e) What is the efficiency of the plank?

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IriamAbhigyan Martin Ninama