A garden hose of internal diameter ends in a nozzle whose circular exit has diameter
PHYSICS · Multi-part · Fermi University Physics · Fluids & Continuum Physics · Kinematics, conservation laws and ideal flow · Kinematics, conservation laws and ideal flow
Fluids and Continuum Physics, Ch Conservation of mass, momentum and energy
Problem
A garden hose of internal diameter 20mm ends in a nozzle whose circular exit has diameter 8.0mm. Water of density 1000kgm−3 flows steadily through it at a volume flow rate Q=0.60litres−1. Take the flow as incompressible, with the speed uniform across the hose bore and across the nozzle exit. The horizontal jet from the nozzle strikes a large flat rigid plate held at right angles to the jet a short distance away, and the water then runs away sideways in the plane of the plate. Neglect the weight of the water in the control volume (it acts vertically) and take the jet and the water leaving the plate to be at atmospheric pressure, so that all gauge pressures on the open faces of the control volume are zero.
((a)) Find the speed of the water in the hose and the speed of the jet at the nozzle exit.
((b)) Find the magnitude of the horizontal force the jet exerts on the plate.