WBJEE · Physics · Work Power Energy
A body starts from rest, under the action of an engine working at a constant power and moves along a straight line. The displacement s is given as a function of time ( \(f\) as
- A \(s=a t+b t^{2}, a\) and \(b\) are constants
- B \(s=b t^{2}, b\) is a constant
- C \(s=a t^{3 / 2},\) a is a constant
- D \(s=a t,\) a is a constant
Answer & Solution
Correct Answer
(C) \(s=a t^{3 / 2},\) a is a constant
Step-by-step Solution
Detailed explanation
Given, Power \((P)=\) constant Kinetic Energy (KE) \(=\frac{1}{2} m v^{2}\) We know that, \(P=\frac{K E}{\Delta t} \Rightarrow P=\frac{m v^{2}}{\Delta t}\) \(\because P=\) constant. Hence, velocity of the body \(v \propto \sqrt{t}\)...(i) As, Velocity…
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