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1) A system contains 0.15 m of air at 4 bar and 150 C. A reversible adiabatic expansion takes place till thepressure falls to 1.01 bar. The gas is then heated at constant pressure till the enthalpy increases by 62 KJ.Calculate the total work and heat transfer and change in entropy. Draw the process on P-v and T-sdiagrams.

2) A turbine operates under steady flow condition receiving steam at the following state: pressure=1.2MPa

temp=188C, enthalpy= 2785KJ/Kg, velocity= 3.3 m/s and elevation=3m. the stem leaves the turbine at the

following state: pressure=20 KPa, enthalpy= 2512KJ/Kg, velocity= 100 m/s and elevation=0 m. heat is lost to thesurroundings at the rate of 0.29KJ/s. if the rate of steam flow through the turbine is 0.42 Kg/s, what is the power

output of the turbine in KW? (or)3) A gas of mass 1.5 kg undergoes a quasi-static expansion which follows a relationship P=a+bV, where a and b areconstants. The initial and final pressures are 100kpa and 200kpa respectively and the corresponding volumes are0.2m and 1.2 m. The specific internal energy of the gas is given by the relation u=1.5pV 85 kJ/kg. Where p is an

Kpa and V is in m. Calculate the net heat transfer and the maximum internal energy of the gas attained duringexpansion.

4) A reversible heat engine operating between reservoirs at 900K and 300K drives a reversible refrigeratoroperating between reservoirs at 300K and 250K. the heat engine receives 1800KJ heat from 900K

reservoir. The net output from the combined engine refrigerator is 360KJ. Find the heat transferred to therefrigerator and the net heat rejected to the reservoir at 300K.

5. Explain and derive carnot cycle and its efficiency.

6 0.1 m3of an ideal gas at 300 K and 1 bar is compressed adiabatically to 8 bar. It is then cooled atconstant

volume and further expanded isothermally so as to reach the condition from where itstarted. Calculate:(i) Pressure at the end of constant volume cooling.

(ii) Change in internal energy during constant volume process.(iii) Net work done and heat transferred during the cycle. Assume cp = 14.3 kJ/kg K and cv = 10.2 kJ/kg K.

7) A stone of 20 kg mass and a tank containing 200 kg water comprise a system. The stone is 15 m above thewater level initially. The stone and water are at the same temperature initially. If thestone falls into water,

then determine U, PE, KE, Q and W, when (i) The stone is about to enter the water,(ii) The stone hascome to rest in the tank, and (iii) The heat is transferred to the surroundings in such an amount that thestone and water come to their initial temperature.

8) A fluid system undergoes a non-flow frictionless process following the pressure-volume relationAs wherep is in bar and V is in m3. During the process the volume changes from0.15 m3 to 0.05 m3 and thesystem rejects 45 kJ of heat. Determine:(i) Change in internal energy;(ii) Change in enthalpy.

1. Define the term Quasi static process.

2. Define thermodynamic system

3.

Define point function.

4. What is boundary?.

5. Define Clausius statement.

6. State Carnot theorem.

7. Explain entropy?

8. Write the term of open and closed systems.9. State Zeroth law of thermodynamics.

10.Define thermodynamic equilibrium.11.Explain homogeneous and heterogeneous system.

12.What are the assumptions made on heat engine?13.Explain the term source and sink.14.

What is reversed Carnot heat engine? What are the limitations of Carnot cycle?