A fluid coupling operates with oil flowing in a closed circuit. The device consists of two elements, the primary and secondary, each making up one-half of a torus, as shown in the Figure below. The input power is 100 hp, and input rotational speed is 1800 rpm. The output rotational speed is 1200 rpm. (a) Evaluate both the efficiency and output power of this device, (b) At what rate must energy as heat be transferred to the cooling system, to prevent a temperature rise of the oil in the coupling? Flow passage Flow passage DOOOOO Section A-A 10000000000 1000000000 24 Section B-B b Impeller R. Input shaft Runner Output shaft 26