Friction loss is defined as which description?

• A. Loss of pressure in terms of feet of head per unit of pipe length
• B. Internal resistance
• C. Loss of pressure in terms of feet of hand per unit of pipe length
• D. Temperature change

Answer: (C)

Friction loss describes how much pressure energy is lost due to the walls of the pipe as water flows. This loss is quantified as feet of head—the height a column of water would reach if that pressure were converted to potential energy—and it is expressed per unit length of pipe. That combination, feet of head per unit length, lets you compare how different pipe lengths or configurations affect the pressure drop caused by friction. The other ideas don’t capture this specific energy-and-length relationship: internal resistance is too vague to specify how pressure translates to height, and temperature change isn’t about pressure loss from friction.