What will be the loss due to friction in a single line of 3" hose with a length of 400 ft carrying 300 gallons of water per minute?

To determine the loss due to friction in a 3-inch hose carrying 300 gallons of water per minute over a distance of 400 feet, we consider the factors that contribute to friction loss. The size of the hose and the flow rate of the water are critical in calculating this loss.

The friction loss in fire hoses can usually be found using standardized equations or charts that relate the diameter of the hose, the length of the hose, and the flow rate to the resulting pressure loss. Larger diameter hoses (like 3 inches) typically have lower friction losses than smaller ones, and shorter lengths have less resistance compared to longer lengths.

In this case, with the flow rate at 300 gallons per minute, when we refer to hydraulic calculations or friction loss charts, we find that a 3-inch hose at this flow rate over a distance of 400 feet yields a friction loss of approximately 34 psi. This value aligns with the referenced data, confirming that option C is the accurate answer for this scenario.

Using industry-standard guidelines allows for consistency and reliability in understanding how the hose's specifications affect performance, thus illustrating why the choice of 34 psi is the correct answer in this context.