Question

Engine of a car supplies constant power to the wheels of car, then

• A. displacement of the car is proportional to $t^2$.
• B. acceleration of the car is proportional to $t^{-1}$.
• C. velocity of the car is proportional to $t^{1/2}$.
• D. displacement of the car is proportional to $t^3$.

Answer 1

The correct option is C velocity of the car is proportional to $t^{1/2}$.

$P=F\times v$
$=ma\times v$
$=m\frac{v}{t}\times v$
$\frac{Pt}{m}=v^2$
$v\propto \sqrt{t}$