[بريق انثى]

. A 5.0-kg box is raised a distance of 2.5 m from rest by a vertical
applied force of 90 N. Find (a) the work done on the box by the applied
force, and (b) the work done on the box by gravity.

Solution

Wg = -mg d = - 5 x 9.8 x 2.5= -122.5 J

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