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A body of mass 2 kg is moving along x-direction such that its displacement as function of time is given by x(t) = t2 + t + m, where = 1 m/s2, = 1 m/s and = 1 m. The work done on the body during the time interval t = 2 s to t = 3 s, is J.
(2) 24
x = t2 + t + 1
v = dxdt = 2t + 1
v(2) = 5 m/s, v(3) = 7 m/s
Work–energy theorem: W = K = 12m(v32 - v22)
= 12 2 (49 - 25)
W = 24 J
Answer: (2)
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