Q. What is the smallest radius of a circle at which a cyclist can travel if its speed is $36\ kmh^{- 1}$, angle of inclination 45${^\circ}$ and $g = 10ms^{- 2}$?
A) 20 m
B) 10 m
C) 30 m
D) 40 m
Explanation
(b) From, $\tan{\theta = \frac{v^{2}}{rg}}$
$r = \frac{v^{2}}{g\tan\theta} = \frac{10 \times 10}{10 \times \tan{45{^\circ}}} = 10\ m$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.