While a person lifts a book of mass 2 kg from the floor to a tabletop, 1.5 m above the floor, how much work does the gravitational force do on the booK?

While a person lifts a book of mass 2 kg from the floor to a tabletop,

1.	While a person lifts a book of mass 2 kg from the floor to a tabletop, 1.5 m above the floor, how much work does the gravitational force do on the booK?
Answer» `-30J` `-15J` `0`J 15J Solution :`W=DeltaK=-DeltaU`. The GRAVITATIONAL force points downward while the book's DISPLACEMENT is UPWARD. THEREFORE, the work done by gravity is -mgh=-(2kg)(10N/kg)(1.5)m=-30J.

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While a person lifts a book of mass 2 kg from the floor to a tabletop, 1.5 m above the floor, how much work does the gravitational force do on the booK?

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