JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A body of mass \(0.5\, kg\) travels on straight line path with velocity \(v =\left(3 x ^{2}+4\right) m / s\). The net workdone by the force during its displacement from \(x =0\) to \(x =2\, m\) is\(.......J\)
- A \(64\)
- B \(60\)
- C \(120\)
- D \(128\)
Answer & Solution
Correct Answer
(B) \(60\)
Step-by-step Solution
Detailed explanation
\(v _{ i }=3\left(0^{2}\right)+4=4\) \(\cong x =0\) \(v _{ F }=3(2)^{2}+4 \cong x =2\) \(=16\) \(W =\Delta K =\frac{1}{2} m \left(16^{2}-4^{2}\right)\) \(=\frac{1}{2} \times \frac{1}{2}(256-16)\) \(=\frac{240}{4}=60\,J\)
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