Reg No.: Name:

D7148

Total Pages: 2

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
THIRD SEMESTER B.TECH DEGREE EXAMINATION, DECEMBER 2017

Course Code: ME205
Course Name: THERMODYNAMICS (MA, ME, MP, AN)

Max. Marks: 100 Duration: 3 Hours

PART A
Answer any three full questions, each carries 10 marks. Marks

a) Define property of a system with any two examples. Why thermodynamic (3) properties
are taken as coordinates in thermodynamics?

b) Explain free expansion? Why the displacement work is absent in free expansion?

(4)

c) List any 6 applications of thermodynamics. (3)
a) What is PMM1? Why it is not possible? (3) b) Define enthalpy. Prove that for ideal gas
enthalpy is a function of temperature (3) alone.
c) Explain the working of thermocouple with neat sketch. (4)

a) A rigid tank of 2m*initially contains air at 100kPa and 25°C. The tank is

connected to a supply line which contains air at 600kPa and 25°C through a valve. The
valve is opened and air is allowed to enter the tank until the pressure (6) in the tank
reaches the line pressure at which the valve is closed and the temperature of the air inside
the tank at this instant measures 80°C. Determine (a) the mass of air that has entered the
tank and (b) the amount of heat transfer.
b) What is total energy of a system? Prove that total energy is thermodynamic (4)
property of a system.
a) Derive steady flow energy equation. (5)
b) In an adiabatic gas turbine, air expands at 1200kPa and 500°C 10 100kPa and
150°C. Air enters the turbine with a velocity of 40m/s through an opening of area (5)
0.2m? and exhausts through a 1m? opening. Determine (a) mass flow rate of air through
the turbine and (b) the power produced by the turbine.
PART B
Answer any three full questions, each carries 10 marks.
a) Give two statements of second law of thermodynamics and prove its equivalence (5)
b) State and explain principle of increase of entropy. Discuss its physical significance.

(5)

a) State and prove Clausius inequality. (6)

b) What is meant by (i) exergy (ii) dead state (iii) availability (4)

a) State and prove Carnot’s theorem. (5)

b) Define dryness fraction. Draw the p-v-T surface of a substance that contracts on
(5) freezing.

Derive the expression for availability of flow process. (10)

Page 1 of 2