0.09m cube of a fluid at 0.7bar are compressed reversibly to a pressure of 3.5bar according to law pvn=constant. the fluid is then heated reversibly at a constant volume until the pressure is 4bar, the specific volume is then 0.5mcube/kg a reversibly expansion according to a law pv2=constant restores the fluid to its initial state. compute the mess of the Fluid present, the value of n in the first process, and the networkdone on or by fluid in the cycle

To save energy, the air supply to a 2000 ft office has been shut off overnight and the room temperature has dropped to 40°f. in the morning, the thermostat is reset to 70°f and warm air at 120 f begins to flov in at 200ft'/min. the air is well mixed within the room, and an equal mass flow of air at room temperature (changing with time) is withdrawn through a return duct. the air pressure is nearly 1 atm everywhere. ignoring heat transfer with the surroundings and kinetic and potential energy effects, estimate how long it takes for the room temperature to reach 70°f. plot the room temperature as a function of time.