Q. A car round an unbanked curve of radius 92 m without skidding at a speed of $26\ ms^{- 1}$. The smallest possible coefficient of static friction between the tyres and the road is
A) 0.75
B) 0.60
C) 0.45
D) 0.30
Explanation
(a) Here, $r = 92\ m,\ v = 26\ ms^{- 1},\mu = ?$
As $\frac{mv^{2}}{r} = F = \mu R = \mu\ mg$
$\mu = \frac{v^{2}}{rg} = \frac{26 \times 26}{92 \times 9.8} = 0.75$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.