Q182 / 200 · WBJEE 2013 · Physics

A particle is acted upon by a constant power. Then, which of the following physical quantity remains constant?

A
Speed
B
Rate of change of acceleration
C
Kinetic energy
Correct answer
D
Rate of change of kinetic energy

Solution

We have Power $=$ Rate of doing work $=\frac{d W}{d t}$ or, $\quad P=\frac{d W}{d t}=$ rate of change in $\mathrm{KE}$ i.e., $\quad P=\frac{d W}{d t}=\frac{d(\mathrm{KE})}{d t}=$ constant

Hence, the correct answer is option: 'D'.

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