Q. A constant power p is applied to a car starting from rest. If v is the velocity of the car at time t, then
A) $v \propto t$
B) $v \propto \frac{1}{t}$
C) $v \propto \sqrt{t}$
D) $v \propto \frac{1}{\sqrt{t\ \ }}$
Explanation
(c) Power,
$p = m \times a \times v$
$p = m \times \frac{v^{2}}{t}$
If p is constant, then for a given body $v^{2} \propto \sqrt{t}$
Or $v \propto \sqrt{t}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.