Which statement about friction loss and elevation head is true?

Which statement about friction loss and elevation head is true?

• A. Friction loss is pressure drop from water moving through hose and fittings; elevation head is the additional pressure needed to lift water to the target height.
• B. Friction loss and elevation head both decrease PDP.
• C. Friction loss is only from hoses; elevation head is the same as nozzle pressure.
• D. They do not affect PDP.

Answer: (A)

Friction loss and elevation head are two kinds of head losses that consume pump pressure before water reaches the nozzle. Friction loss is the pressure drop caused by water moving through hose and fittings; it depends on flow rate, hose length, size, and fittings. Elevation head is the additional pressure required to lift water to the target height—the vertical rise from pump to discharge point. This statement is the best because it plainly defines each term, giving you the foundation to understand how they affect the pressure the pump must provide. In practice, both factors reduce the pumped discharge pressure (PDP) since part of the pump’s effort is used to overcome friction and to lift water to height. The other options mix up the concepts or misstate what each term covers (for example, friction loss isn’t limited to hoses, elevation head isn’t nozzle pressure, and they do affect PDP).

Friction loss and elevation head are two kinds of head losses that consume pump pressure before water reaches the nozzle. Friction loss is the pressure drop caused by water moving through hose and fittings; it depends on flow rate, hose length, size, and fittings. Elevation head is the additional pressure required to lift water to the target height—the vertical rise from pump to discharge point. This statement is the best because it plainly defines each term, giving you the foundation to understand how they affect the pressure the pump must provide. In practice, both factors reduce the pumped discharge pressure (PDP) since part of the pump’s effort is used to overcome friction and to lift water to height. The other options mix up the concepts or misstate what each term covers (for example, friction loss isn’t limited to hoses, elevation head isn’t nozzle pressure, and they do affect PDP).