What phenomenon occurs as water flows through a hose and loses pressure?

Friction loss refers to the reduction in pressure that occurs when water flows through a hose due to the interaction between the moving water and the internal surface of the hose. As the water travels, it encounters resistance from the hose material and any bends or fittings along the way, which leads to a loss of energy and, consequently, pressure. This phenomenon is significant in fire and emergency services, as it affects the efficiency of water flow during firefighting operations. Understanding friction loss is essential for firefighters to ensure adequate water supply and pressure at the nozzle, which is crucial for effective firefighting.

The other concepts, such as back pressure, pressure drop, and volume loss, relate to different aspects of fluid dynamics and pressure relationships but do not specifically define the loss of pressure due to the internal resistance encountered while water is moving through a hose.