Air at 1.02 bar, 22 0C, initially occupying a cylinder volume of 0.015 m3 , is compressed reversibly and adiabatically by a piston to a pressure of 4.8 bar. The change in internal energy decreases to 65 kJ. Assume γ of air = 1.4 Calculate: a) The final temperature. b) The final volume. c) The work done. d) Heat transfer

Air at 20°C and 7 bar is contained in a rigid tank of 0.57 m3 volume capacity. The tank is provided with a valve that opens at a pressure of 8.5 bar and remains open until the pressure drops to 8.15 bar. Determine: a) Air temperature just before the valve opens b) Mass of air lost due to fire.

a) Unit mass of a fluid at pressure of 3 bar, and specific volume of 0.19 +0.2× 16 m3/kg, contained in a cylinder behind a piston expands reversibly to a pressure of 0.8 bar according to law p = c/v2, where c is a constant. Calculate the work done during the process.

4. A mass of 0.05 kg of carbon dioxide (molar mass 44 kg/kmol), occupying a volume of 0.03 m³ at 1.025 bar, is compressed reversibly until the pressure is 6.15bar. Calculate the final temperature, the work done on the CO2, and the heat supplied: i) 1.4 = constant when the process is according to a law pv ii) when the process is isothermal iii) when the process takes place in a perfectly thermally insulated cylinder. Use Cp of CO2 as 939 J/kgK, which is the cp at 400K as per tables of properties page 17.

Q3: Air undergoes a three-process cycle. if the processes are :1→ 2: constant- pressure expansion .2→ 3: constant volume 3 → 1: constant-temperature compression .The necessary information is T1 = 100°C, T2 = 600°C, and P1 = 200 kPa. R=0.287 KJ/kg.K 1) Find the net work done for 1 kg A: 32.5 KJ B: 42.5 KJ C: 52.5 KJ D: 62 KJ

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awuIs 2 kg of air undergoes a power cycle undergocs a power cycle consisting of the following processes: Process 1-2: Constant-temperature expansion from p, = 4 bar, v, = 1 m³ /kg, to p2 = 2 bar, v2 = 2 m3/kg. Process 2-3: Constant-pressure compression to T3 = 696.9 K. Process 3-1: Constant-volume heating to state 1. Assume ideal gas behavior and neglect kinetic and potential energy effects. Show that T; = 1393.7 K and find T Sketch the cycle on a T-v diagram and label the states. Find the work done and heat transferred during cach process to complete this chart: b C. Process W (kJ) Q (kJ) iti 1-2 2-3 3-1 TOTAL Find the thermal efficiency of the cycle. For an energy balance on the entire cycle (1-2-3-1), what should the change in system energy be? Does that hold in this case? Add a Caption Pedro Castaño shared with you > Wednesday • Feb 23, 2022•7:24 PM Adjust IMG_7188 Apple iPhone 12 Pro Max НEIF Wide Camera – 26 mm f1.6 3 MP • 1914 × 1728 • 3.5 MB i

For open systems, entropy can be transferred by a) heat transfer only. b) mass transfer only. c) both heat and mass transfer.