Enter the cross-sectional area of the nozzle and the pressure differential at the nozzle into the calculator to determine the nozzle reaction force.

## Nozzle Reaction Force Formula

The following equation is used to calculate the Nozzle Reaction Force.

NR = P * NA
• Where NR is the nozzle reaction force (lbf)
• P is the pressure at the nozzle (psi)
• NA is the nozzle cross-sectional area (in^2)

To calculate the nozzle reaction force, multiply the pressure by the nozzle area.

## What is a Nozzle Reaction Force?

Definition:

The nozzle reaction force is the force generated by the water pressure as it exits the nozzle. This is the force that pushes the fire hose back.

## How to Calculate Nozzle Reaction Force?

Example Problem:

The following example outlines the steps and information needed to calculate Nozzle Reaction Force.

First, determine the pressure differential at the nozzle opening. In this example, the pressure is 100 PSI.

Next, determine the cross-sectional area of the nozzle opening. In this case, the cross-sectional area is 5 square inches.

Finally, calculate the nozzle reaction force using the formula above:

NR = P * NA

NR = 100 * 5

NR = 500 lbf