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Force F on a particle moving in a straight line varies with distance d as shown in figure. [figure] The work done on the particle during its displacement of 12 m is
(4) 13 J
Work done = area under the F–d graph
From d = 0 to 3 m: F = 0 W1 = 0
From d = 3 to 7 m (rectangle): W2 = 2 (7 - 3) = 8 J
From d = 7 to 12 m (triangle): W3 = 12 (12 - 7) 2 = 5 J
W = 0 + 8 + 5 = 13 J
Answer: (4)
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