(Density of water : $10^{3}\, kg / m ^{3}$ )
$R _{ e }=\frac{\rho vD }{\eta}$
$[\rho \rightarrow$ density of fluid ;
$\eta \rightarrow$ coefficient of ;
$v \rightarrow$ velocity of flow ;
$D \rightarrow$ Diameter of pipe$]$
From NCERT
If $R _{ e }<1000 \quad \rightarrow$ flow is steady
$1000< R _{ e }<2000 \rightarrow$ flow becomes unsteady
$R _{ e }>2000 \rightarrow$ flow is turbulent
$R _{ e \text { initial }}=10^{3} \times \frac{0.18 \times 10^{-3}}{\pi \times\left(0.5 \times 10^{-2}\right)^{2} \times 60} \times \frac{1 \times 10^{-2}}{10^{-3}}$
$=382.16$
$R _{ efinal }=10^{3} \times \frac{0.48 \times 10^{-3}}{\pi \times\left(0.5 \times 10^{-2}\right)^{2} \times 60} \times \frac{1 \times 10^{-2}}{10^{-3}}$
$=1019.09$
|Take atmospheric pressure $=1.0 \times 10^5 \mathrm{~N} / \mathrm{m}^2$, density of water $=1000 \mathrm{~kg} / \mathrm{m}^3$ and $g=10 \mathrm{~m} / \mathrm{s}^2$. Neglect any effect of surface tension.]
