Q3: A mass of air at 330 °C, contained in a cylinder expanded polytropically to five times its initial volume and 1/8th its initial pressure which is 1 bar. Calculate the value of the expansion index, and the work done per unit mass of air.

1. What should be the water line gage pressure in the ground floor of a building so that water can rise up in the fifth floor which is 15m high? 2. Determine the volume occupied by a 2kg steam at 500kPa, under the following conditions: (a) pressure state (b) pure vapor state (c) 20% moisture content (d) 20% dry When P (kPa) = 500, T (°C) = 151.86, Vf (m³/kg) = 0.0019 and Vg (m³/kg) = 0.3749   3. An automobile tire contains a certain volume of air at 205kPa, and 20°C. The barometric pressure is 100kPa, if due to maintaining conditions the temperature of the air in the tire rises to 70°C, what will be the gage pressure? Assume that the air is an ideal gas and that the tire does not stretch.

It seems pressure should be converted into Absolute, While applying it to Ideal gas equation.

During processing in a steel mill, a 375kg steel casting at 800 degrees  is quenched by plunging it into a 500-gal oil bath, which is initially 75 degrees . After the casting cools and the oil bath warms , what is the final tempertature of the two? The weight per unit volume of the oil is 7.5 lb/gal.