MCQ
A particle is acted by a constant power. Then, which of the following physical quantity remains constant?
- ASpeed.
- BRate of change of acceleration.
- CKinetic energy.
- ✓Rate of change of kinetic energy.
✓
Answer
Correct option: D.
Rate of change of kinetic energy.
By definition, $\text{p}\frac{\text{dW}}{\text{dt}}$
$\because$ Work done $=$ Kinetic energy
$\Rightarrow\text{p}=\frac{\text{dW}}{\text{dt}}$
$=\frac{\text{d(KE)}}{\text{dt}}=\text{constant}$
$\because$ Work done $=$ Kinetic energy
$\Rightarrow\text{p}=\frac{\text{dW}}{\text{dt}}$
$=\frac{\text{d(KE)}}{\text{dt}}=\text{constant}$
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