Turbines 8. (10 pts) A hydraulic turbine is used to power a lift in a remote construction site, as shown in Fig. 1. The turbine is supplied with water from a large elevated reservoir with a head H = 15 m. The flow rate is increased gradually and found to be Q = 41/s, when the load starts getting lifted. The turbine shaft is coupled to a pulley with a diameter d = 0.40 m through a speed-reducing gearbox with a gear ratio 10:1. A steel cable is attached to this pulley and passes through additional pulleys, shown in the figure, so that, as the turbine operates, the cable lifts the load that has a mass m = 100 kg. Assume that the turbine efficiency is roughly 80%, the gearbox efficiency is 75% and neglect frictional losses in any other part of this system. h m H Q Fig. 1: Sketch of the turbine-powered lift system. (a) Determine the rotational speed of the pulley, in rpm, when the load starts getting lifted. (b) Determine the corresponding rotational speed of the turbine, in rpm. (c) Determine the time it would take for the load to be lifted to a platform located at h = 8 m.