True or False: A smaller pipe diameter results in greater friction loss.

• A. True
• B. False
• C. Only in certain conditions
• D. It depends on the water temperature

Answer: (A)

A smaller pipe diameter indeed leads to greater friction loss in the context of fluid dynamics. This phenomenon occurs because friction loss is influenced by the surface area in contact with the fluid as it flows through the pipe. In narrower pipes, the fluid has less space to move, which increases the velocity of the fluid but also increases the resistance against the walls of the pipe. This resistance manifests as friction loss, which can cause pressure drops in the system.

Additionally, when water, or any fluid, flows through a pipe, it experiences turbulence, especially at smaller diameters. This turbulence contributes further to the friction losses, as the inner surface of the pipe and the fluid interact more aggressively than they would in a larger pipe.

Considering other aspects, while factors like the length of the pipe, the roughness of the interior surface, and the flow rate also impact friction loss, the fundamental principle remains that a decrease in pipe diameter generally leads to an increase in friction loss. Therefore, the statement is true.