Final answer:
The physical property determining gas flow in a flowmeter at different flow rates is the Reynolds number. Viscosity is a fluid's resistance to flow, and pressure drops due to resistance can be calculated using Poiseuille's law.
Step-by-step explanation:
The physical property that determines gas flow at low flow vs high flow in a flowmeter is the Reynolds number. This dimensionless number indicates whether the flow is laminar or turbulent. Viscosity is a measure of a fluid's resistance to flow. Fluids with low viscosity, like juice, flow easily, while those with high viscosity, like syrup, flow more slowly. Poiseuille's law can be used to calculate flow and resistance, where the flow (Q) through a circular pipe is inversely proportional to the viscosity of the fluid (μ) and directly proportional to the pressure difference (ΔP) across the pipe and the fourth power of the pipe's radius (r).
Pressure drops in a system due to resistance, which is affected by factors such as viscosity, length of the path, and the diameter of the tube through which the fluid flows.