COMEDK · Physics · 6. Work Power Energy
An object of mass \(3\text{ kg}\) moves due to an applied constant force such that its position along X axis is given by \(x = \dfrac{t^{\mathrm{2}}}{3}\) where \(x\) is in meters and \(t\) in seconds. The work done in 1 second is
- A 1 J
- B 2 J
- C 6 J
- D \(\dfrac{2}{3}\) J
Answer & Solution
Correct Answer
(D) \(\dfrac{2}{3}\) J
Step-by-step Solution
Detailed explanation
\(x = \dfrac{t^2}{3} \Rightarrow v = \dfrac{dx}{dt} = \dfrac{2t}{3}\) At \(t = 0\): \(v_i = 0\), at \(t = 1\) s: \(v_f = \dfrac{2}{3}\) m/s By work-energy theorem:…
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