JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A body of mass \(2\, kg\) is driven by an engine delivering a constant 10.Power \(1\, J / s\). The body starts from rest and moves in a straight line. After \(9\) seconds, the body has moved a distance (in \(m )\)
- A \(28\)
- B \(25\)
- C \(20\)
- D \(18\)
Answer & Solution
Correct Answer
(D) \(18\)
Step-by-step Solution
Detailed explanation
\(P=m a v\) \(m \frac{d v}{d t} v=P\) \(\int_{0}^{v} v d v=\frac{P^{t}}{m} \int_{0}^{t} d t\) \(\frac{v^{2}}{2}=\frac{P t}{m} \Rightarrow v=\left(\frac{2 P t}{m}\right)^{1 / 2}\) \(\frac{d x}{d t}=\sqrt{\frac{2 P}{m}} t^{1 / 2}\)…
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