Experimental ProcedureThe apparatus is first levelled and the lever brought to the balanced position (asindicated by the tally), with the jockey weight at its zero setting. Note the weight ofthe jockey, and the following dimensions: diameter of the nozzle, height of the vaneabove the tip of the nozzle when the lever is balanced, and distance from the pivot ofthe lever to the centre of the vane.Water is then admitted through the bench supply valve, and the flow rate increased tothe maximum. The force on the vane displaces the lever, which is then restored to itsbalanced position by sliding the jockey weight along the lever. The mass flow rate isestablished by collection of water over a timed interval. Further observations are thenmade at a number reducing flow rates. About eight readings should suffice.The best way to set the conditions for reduced flow rate is to place the jockey weightexactly at the desired position, and then to adjust the flow control valve to bring thelever to the balanced position. The condition of balance is thereby found withouttouching the lever, which is much easier than finding the point of balance by slidingthe jockey weight. Moreover, the range of settings of the jockey position may bedivided neatly into equal steps.The experiment should be run twice, first with the flat plate and then with thehemispherical cup.