Question 247: Work, Energy and Power & Circular Motion

Question

On dry road, the maximum speed of a vehicle along a circular path is '$V$'. When the road becomes wet, maximum speed becomes $\frac{\mathrm{V}}{2}$. If coefficient of friction of dry road is '$\mu$' then that of wet road is

Accepted Answer

The equation for maximum velocity is
$\mathrm{V}=\sqrt{\mu \mathrm{rg}}$ .... (i)
When the road becomes wet the equation becomes
$\frac{\mathrm{V}}{2}=\sqrt{\mu^{\prime} \mathrm{rg}}$ ..... (ii)
Dividing equation (i) with equation (ii),
$\begin{aligned}
& {V \over {{V \over 2}}} =\frac{\sqrt{\mu \mathrm{rg}}}{\sqrt{\mu^{\prime} \mathrm{rg}}} \
	herefore \quad & 2 =\frac{\sqrt{\mu}}{\sqrt{\mu^{\prime}}} \
	herefore \quad & \mu^{\prime} =\frac{\mu}{4}
\end{aligned}$

Answer

$\frac{2 \mu}{3}$

Answer

$\frac{\mu}{4}$

Answer

$\frac{\mu}{3}$

Answer

$\frac{3 \mu}{4}$

Work, Energy and Power & Circular Motion

On dry road, the maximum speed of a vehicle along a circular path is 'V'. When the road becomes wet, maximum speed becomes \frac{\mathrm{V}}{2}. If coefficient of friction of dry road is '\mu' then that of wet road is

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