A Pelton impulse turbine has blades designed so that the direction of the incoming water jet with speed u is reversed. If the speed of the blades is u_c then, relative to the blade, the magnitude of the total change in the velocity of the jet is 2(u- u_c).
If the flow of water is Q m^3s^-1 find expressions for the force on the blade and the power produced. Hence determine the maximum power output.