Question

Streamline flow is more likely for liquids with

• A. low density and low viscosity
• B. high density and high viscosity
• C. high density and low viscosity
• D. low density and high viscosity

Answer 1

Answer: (D)

Streamline flow is more likely for liquids having low density. We know that greater the coefficient of viscosity of a liquid more will be the velocity gradient, hence each of flow can be differentiated streamline flow is related with critical velocity. The critical velocity is that velocity of liquid flow up to which its flow is streamlined and above which its flow becomes turbulent.As critical velocity $\left(\eta \right)$ and density $\left(\rho \right)$ of the liquid as $\left(V_c\right)\propto \frac{\eta }{\rho }$. Hence if the density will be low and viscosity will be high, the value of critical velocity will be more.