The "impact of jets" testing apparatus is used to measure the force produced by the jet impinging on the reaction vane. It consists of a water supply pipe surrounded by a transparent plastic shield fitted with a top assembly and flat plate reaction (turning) vane. In operation, water from the hydraulic bench is fed into the unit and a vertical water jet is produced and deflected by the reaction vane. The vane is supported by a pivoted beam, restrained by a spring. Adjusting the jockey weight sets the beam to a balanced position. Figure: Schematic of impact of a water jet apparatus (left) and vertical jet of fluid striking a symmetrical vane (right) The impact force by the jet can be also calculated based on the linear momentum change of the jet: Fjet = ņu, (1 – cosB) (1) where ṁ : mass flow rate, uo: velocity that strikes the vane, B:deflected angle of the jet The weight beam was initially at balance with the jockey weight at the zero position. You started the hydraulic bench and increased the mass flow rate to be 0.15 kg/s. You moved the jockey weight until the beam balanced again and the distance y from the zero position, y was 10 mm. 0.00007854m2 3.5 cm Nozzle Area Distance between the nozzle and the impact vane, s Density of water Gravitational acceleration Jockey weight 1000 kg/m3 9.8 m/s2 600 g