Q. A curved road of 50 m radius is banked at correct angle for a given speed. If the speed is to be doubled keeping the same banking angle, the radius of curvature of the road should be changed to
A) 25 m
B) 100 m
C) 150 m
D) 200 m
Explanation
(d) Here, $r = 50\ m$
As tan$\ \theta = \frac{v^{2}}{rg},$ therefore, when speed $v$ is doubled; $r$ must be made 4 times, if $\theta$ remains the same
$\therefore$ New radius of curvature,
$r^{'} = 4r = 4 \times 50\ m = 200\ m$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.