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(i) work done = Area under the graph
= (40x20) + (20 x 10) = (80 x 40)
= 800 + 200 + 3200 = 4200J
(ii) work done = mgh
= 25 x 10 x 12 = 3000J
Energy wasted = (4200 – 3000)J = 1200J
(iii) Friction force between the surfaces. Some work is done against friction
sharon kalunda answered the question on April 2, 2019 at 11:15
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