$R _{ e }=\frac{\rho vD }{\eta}$

$[\rho \rightarrow$ 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

$R _{ e \text { initial }}=10^{3} \times \frac{0.18 \times 10^{-3}}{\pi \times\left(0.5 \times 10^{-2}\right)^{2} \times 60} \times \frac{1 \times 10^{-2}}{10^{-3}}$

$=382.16$

$R _{ efinal }=10^{3} \times \frac{0.48 \times 10^{-3}}{\pi \times\left(0.5 \times 10^{-2}\right)^{2} \times 60} \times \frac{1 \times 10^{-2}}{10^{-3}}$

$=1019.09$