Reynolds Number — MCQ Practice

Water flows through a pipe of diameter $2\,\text{cm}$ with a velocity of $0.5\,\text{m/s}$. Given the density of water is $1000\,\text{kg/m}^3$ and its dynamic viscosity is $10^{-3},\text{Pa} \cdot \text{s}$, calculate the Reynolds number and determine the nature of the flow.

Which of the following changes would lead to an increase in the Reynolds number for fluid flow in a pipe, assuming all other parameters remain constant?

Blood flows through an artery of diameter $0.5\,\text{cm}$ at an average velocity of $0.2\,\text{m/s}$. Given the density of blood is $1060\,\text{kg/m}^3$ and its dynamic viscosity is $4 \times 10^{-3},\text{Pa} \cdot \text{s}$, calculate the Reynolds number. What type of flow is this likely to be?

A fluid flow is observed to be turbulent. If the fluid's density is doubled and its dynamic viscosity is halved, what must happen to the product of velocity and characteristic length ($vD$) to maintain the same Reynolds number?

Which of the following statements about the Reynolds number is INCORRECT?

A fluid with kinematic viscosity $2 \times 10^{-6},\text{m}^2/\text{s}$ flows through a tube of diameter $1\,\text{cm}$. What is the maximum velocity for the flow to remain laminar? (Assume critical Reynolds number for laminar flow is $2000$)