You are supplying Truck 14 to their rear inlet through dual 3" lines, 100' in length each. What is the friction loss if the truck operator needs 190 psi at the inlet and the hydrant pressure is 60?

The friction loss in a hose or piping system is calculated by considering the length and diameter of the hose, the flow rate, and the material through which the fluid is traveling. In this scenario, you are supplying Truck 14 with dual 3" lines that are each 100 feet in length.

To determine the friction loss, you need to account for the total flow requirement and the specific characteristics of the hoses. The correct choice reflects the need for a pressure at the inlet of 190 psi, while the hydrant pressure is only 60 psi. This indicates that there is a significant amount of friction loss that must be overcome to achieve the necessary operational pressure for Truck 14.

When calculating friction loss, if the total friction loss from both lines is calculated and added to the hydrant pressure, it would yield 190 psi at the outlet. Therefore, one would find that the total needed pressure, considering both the inlet requirement and the hydrant supply, leads to the pressure required from the hydrant plus the friction loss reaching the required inlet pressure.

So, the answer of 210 psi corresponds to 190 psi at the inlet plus the required friction loss, confirming that the truck operator will need a total supply pressure of 210 psi to compensate