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Figure 13 shows a model steam turbine that consists of a hollow metal cylindersupported on a vertical axis by two bearings. The cylinder can rotate about thisvertical axis. Initially, the cylinder contains 0.010 kg of water and is stationary. A burner heats thewater which starts to boil. to boll.The cylinder begins to rotate when jets of steam first emerge from the four nozzles.Steam is ejected at the same steady rate from each nozzle.

The water in the cylinder starts to boil at time /= 0 and is completely boiled awayat t = 355 s. Show that during this time the rate of heat transfer to the water in the cylinder isapproximately64 W. specific latent heat of water = 2260 kJ kg Assume that all of the heat transfer takes place through the base of the metal cylinder. Estimate the temperature difference across the base of the cylinder. thermal conductivity of metal = 111 Wm¹K¹ radius r of cylinder = 1.60 x 10-² m thickness of base of the cylinder = 1.2 x 10³ m Show that approximately 7 mg of steam is ejected from each nozzle per second. Explain why the cylinder experiences a resultant torque. Refer to momentum in your answer. Figure 14 shows the variation of the cylinder's rotational frequency with timefrom /= 0 to 1 = 225 s.

Calculate the angular acceleration of the cylinder from 1 = 0 to 1 = 225 s. The ejection of steam from the nozzles exerts a total torque of 1.94 x 10-4 N m on thecylinder. The perpendicular distance R from the nozzle to the axis of rotation, as shown inFigure 13, is 2.5 cm. Calculate the speed at which steam is ejected from one nozzle.

The cylinder experiences a frictional torque. Explain, without calculation, how the magnitude of the frictional torque can bedetermined using data from Figure 15. The moment of inertia of the cylinder is known.

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