Fluids/How do you calculate nozzle velocity head?

We invoke the continuity of flow principle which states that the flow of mass over time is constant. dM/dT = constant..

So if the X-sectional area of the hose is A and of the nozzle is a < A when the flow is dM/dT = rho A dl/dT through the hose it must also be dM/dT = rho a dL/dT through the nozzle. Thus we can set the two equal to each other so we have: rho a dL/dT = rho A dl/dT and dL/dT = (A/a) dl /dT = (A/a) v = V where V is the velocity, in meters per second (if using mks SI units) of the nozzle speed. ANS.

Note that Al = aL = volume of water that flows and volume X density of water means the mass of the water M.

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