Using 5 inch hose to move water results in what friction loss?

Using 5 inch hose to move water results in what friction loss?

• A. Very little friction loss
• B. High friction loss
• C. No friction loss
• D. Unpredictable friction loss

Answer: (A)

Friction loss scales with how fast water must move through the hose and how long it travels. A 5 inch hose provides a much larger interior area, so for the same discharge the water velocity is lower and the contact with the hose walls is less intense. That means the resistance the water experiences per foot is reduced, giving a small overall pressure drop per length. In firefighting practice, this translates to very little friction loss for 5 inch hose at typical flows, though not zero and it will rise with higher flows or longer runs. So the best description is that friction loss is very little when using a 5 inch hose to move water.

Friction loss scales with how fast water must move through the hose and how long it travels. A 5 inch hose provides a much larger interior area, so for the same discharge the water velocity is lower and the contact with the hose walls is less intense. That means the resistance the water experiences per foot is reduced, giving a small overall pressure drop per length. In firefighting practice, this translates to very little friction loss for 5 inch hose at typical flows, though not zero and it will rise with higher flows or longer runs. So the best description is that friction loss is very little when using a 5 inch hose to move water.