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(I) work done by force = Fd = 200 x 22.5 = 4500 J
(II) Work done by mass = mgh = 30 x 10 x 7.5 = 2250 J
(III) Work done to friction = work done by force - work done on mass
= 4500 - 2250 = 2250 J
johnmulu answered the question on May 16, 2017 at 08:16
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