Air undergoes an isothermal expansion as an ideal gas in a closed system.  The air pressure increases in the process. True or False?

A piston-cylinder assembly contains a mystery substance that undergoes a series of processes. Process 1-->2: Constant pressure process at 5bar from v1=.07m3/kg to v2=.12m3/kg Process 2->3: Constant volume process to saturated vapor Process 3->4: Constant temperature process to quality of 50% Process 4->5: Constant volume process to 5bar Sketch the processes on Pt, Pv, and Tv, plots. Lable the axes including property values; use closed dots to show the states, use solid lines to connect the states, add number and arrows to make clear the states numbers and process directions. Could this be considered a thermodynamic cycle? Why or why not?

For adiabatic process, pressure before and after the process are 8000 kN/m2 and 2 bar respectively. The volume before and after the process are 4000 mm and 40 cm³ respectively. Then the adiabatic index is O A. None of the answers given O B. 3.4 O C. 2.4 O D. 1.4

N = 0 An insulated tank of volume 10+(10+N)/25 m and with a valve was filled with perfect tri- atomic gas at pressure 10 bar, where N is equal to the last two digitals in your student's ID number. Initially the valve was closed. A paddle wheel was mounted inside the tank and was run by 20 kW engine. The paddle wheel was turn on and at the same time the exit valve was opened. The gas temperature was constant though the whole process (due to very slow flow) and equal to 300 K. Calculate the time needed to decrease the pressure in the tank to 5 bar.