Question

A biker is moving with a speed of $15\text{m/s}$ on a flat road. The coefficient of friction between the wheels of the bike and the road is $0.4$. If he approaches a curve, what is the minimum radius of the turn that he can take safely?

• A. $56.25\text{m}$
• B. $22.5\text{m}$
• C. $562.5\text{m}$
• D. $225\text{m}$

Answer 1

The correct option is A $56.25\text{m}$

As we know that necessary centripetal force is provided by the friction between the road and the tyres
$\therefore \frac{m{v}^2}{r}=f\le \mu mg$
$\Rightarrow r\ge \frac{v^2}{\mu g}=\frac{{15}^2}{0.4\times 10}$
$\Rightarrow r\ge 56.25\text{m}$