Question

1. (25 pts) Liquid water is being heated in a vertical piston-cylinder device. The piston has a mass of 20 kg and a cross sectional area of 100 cm². (a)

If the local atmospheric pressure is 101 kPa, determine the temperature at which the water will start boiling. (b) At an instant during boiling, the height of the liquid water in the cylinder is reduced by half. Determine the specific volume of the mixture at this instant. Plot the process on T-v diagram. Include the saturated liquid line and the saturated vapor line. Label the initial state as 1 (compressed liquid) and the final state (when liquid height is reduced by half) as state 2.

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