Mechanical Engineering

Determine the volume occupied by 10 kg water at a pressure of 10 MPa and a temperature of (a)5"C, (b)200 "C, (c) 400 "C, (d)800 "C, (e) 1500 "C, and (f)-10 "C. Ans. (a)0.00996 m3 (b)0.0115 m3 (c) 0.2641 m3 (d)0.4859 m3 (e)0.8182 m3 (f)0.01089 m3

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Mechanical Engineering

Two kg of steam at a quality of 0.80 is contained in the volume shown (Fig. 2-8). A spring is then brought in contact with the top of the piston and heat is added until the temperature reaches 500°C. Determine the final pressure. (The force in the spring is Kx, where x is the displacement of the spring. This results in a trial-and-error solution.) Ans. 220 kPa

Fig. 2-8

Fig. 2-8

Mechanical Engineering

Two kg of water is contained in a piston-cylinder arrangement by a 16 000-kg, 2-m-diameter, frictionless piston. See Fig. 2-1. Heat is added until the temperature reaches (a) 400 "C, (b)650 "C, and (c) 140 "C. Calculate the final volume. Ans. (a) 4.134 m3 (b)5.678 m3 (c) 2.506 m3

Mechanical Engineering

Freon 12 is contained in a sealed glass container at 50°C. As it is cooled, vapor droplets arc noted condensing on the sidewalls at 20°C. Find the original pressure in the container. Arts. 650 kPa

Mechanical Engineering

A rigid vessel contains water at 400°F. Heat is to be added so that the water passes through the critical point. What should the quality be at the temperature of 400"F? Am. 0.01728

Mechanical Engineering

Steam with a quality of 0.85 is contained in a rigid vessel at a pressure of 200 kPa. Heat is then added until the temperature reaches (a)400 "C and (b)140 "C. Determine the final pressures. Ans. (a) 415 kPa (h)269 kPa

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Mechanical Engineering

A rigid vessel with a volume of 10 m3 contains a water-vapor mixture at 400 kPa. If the quality is 60 percent, find the mass. The pressure is lowered to 300 kPa by cooling the vessel; find mKand m,. Am. 35.98 kg. 16.47 kg, 19.51 kg

Mechanical Engineering

The temperature of 10 Ib of water is held constant at 205°F. The pressure is reduced from a very high value until vaporization is complete. Determine the final volume of the steam. Ans. 307.2 ft'

Mechanical Engineering

Two kg of saturated water at 125 kPa is completely vaporized. Calculate the volume (a)before and (b) after. Ans. (a)0.002 m3 (b)2.76 m3

Mechanical Engineering

Determine the final volume of a mixture of water and steam if 3 kg of water is heated at a constant pressure until the quality is 60 percent. The pressure is (a)25 kPa and (b)270 kPa.

Ans. (a) 11.6 mZ (h)1.24 m3

Ans. (a) 11.6 mZ (h)1.24 m3