Q. The minimum velocity $\left( {in\ ms}^{- 1} \right)$ with which a car driver must traverse a flat curve of radius of 150 m and coefficient of friction 0.6 to avoid skidding is
A) 60
B) 30
C) 15
D) 25
Explanation
(b) Using the relation
$\frac{{mv}^{2}}{r} = \mu R,\ \ R = mg$
$\frac{{mv}^{2}}{r} = \mu mg \Longrightarrow v^{2} = \mu rg$
$v^{2} = 0.6 \times 150 \times 10$
$v = 30{\ ms}^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.