A series of blades, such as in Example 10.13, moving in the same direction as a water jet of \(25 \mathrm{~mm}\) diameter and of velocity \(46 \mathrm{~m} / \mathrm{s}\), deflects the jet \(75^{\circ}\) from its original direction. What relation between blade velocity and blade angle must exist to satisfy this condition? What is the force on the blade system?

Data From Example 10.13

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Example 10.13 OPTIMUM SPEED FOR IMPULSE TURBINE A Pelton wheel is a form of impulse turbine well adapted to situations of high head and low flow rate. Consider the Pelton wheel and single-jet arrangement shown, in which the jet stream strikes the bucket tangentially and is turned through angle 0. Obtain an expression for the torque exerted by the water stream on the wheel and the corresponding power output. Show that the power is a maximum when the bucket speed, U=Rw, is half the jet speed, V.