Final answer:
The size of a rigid fuel line is determined by its outside diameter, but for fluid dynamics, the inside diameter is also important, such as calculating the Reynolds number to determine flow type.
Step-by-step explanation:
The size of a rigid fuel line is typically determined by its outside diameter (OD). However, for precise applications, such as fluid dynamics calculations, the inside diameter (ID) of the fuel line is also crucial. The distinction between ID and OD is essential for ensuring proper fit and function in engineering systems.
For example, calculating the Reynolds number requires knowledge of the ID for determining whether fluid flow is laminar or turbulent. In the scenario described, the hose carries water at 40.0 L/s with an original ID of 6.40 cm, which then passes through a nozzle with an ID of 3.00 cm. To demonstrate turbulent flow, we'd compute the Reynolds number using the velocity, diameter, and properties of the fluid for both the hose and nozzle. If the Reynolds number exceeds a critical value, typically around 4000, it indicates turbulent flow.