Question

A person wants to drive on the vertical surface of a large cylindrical wooden 'well' commonly known as'death well' in a circus. The radius of the well is 2 meter, and the coefficient of friction between the tyres of the motorcycle and the wall of the well is $0.2,$ the minimum speed the motorcyclist must have in order to prevent slipping should be

• A. $10m/s$
• B. $15m/s$
• C. $1.98m/s$
• D. $25m/s$

Answer 1

The correct option is C $1.98m/s$

$\begin{array}{c}cemtripetalforce=Frictionalforce\\ \frac{m{v}^2}{r}=\mu mg\\ \frac{v^2}{r}=\mu g\\ v=\sqrt{\mu gr}\\ =\sqrt{0.2\times 9.8\times 2}\\ =1.98m/s\end{array}$

Hence,

option $\left(C\right)$ is correct answer.