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A force F acting [figure] on an object varies with distance x as shown here. The force is in N and x in m. The work done by the force in moving the object from x = 0 to x = 6 m is
(2) 13.5 J
Work done = area under the F–x graph from x = 0 to x = 6 m.
Rectangle (0 to 3 m): W1 = 3 3 = 9 J
Triangle (3 m to 6 m): W2 = 12 3 3 = 4.5 J
W = 9 + 4.5 = 13.5 J
Answer: (2)
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