NEETPhysicsWork Energy and PowerMCQ+4 / −1
A body of mass 3 kg is under a constant force which causes a displacement s in metres in it, given by the relation s = t2, where t is in seconds. Work done by the force in 2 seconds is
- A
- B
- C
- D
View written solutionFree
Correct answer: D
Acceleration = d2s/dt2
= 2/3 m/s2
Now force acting on body = mass × acceleration
F = 3 × (2/3) = 2 Newton
Hence displacement in 2 secs
= (1/3) × 2 × 2 = 4/3 m
Finally, work done = 2 × 4/3 = 8/3 J
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