Q. A car moving with a velocity of $10\ m/s$ can be stopped by the application of a constant force $F$ in a distance of $20\ m.\ $If the velocity of the car is $30\ m/s$. It can be stopped by this force in
A) $\frac{20}{3}m$
B) $20\ m$
C) $60\ m$
D) $180\ m$
Explanation
(d) $S \propto u^{2}.$ If $u\ $becomes 3 times then $S$ will become 9 times
$i.e.$ $9 \times 20 = 180m$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.