IES Mechanical Engineering 2011 Solved Question Paper
IES Mechanical Engineering 2011 Solved Question Paper-I01. Which one of the following represents open thermodynamic system?
(A) Manual ice cream freezer (B) Centrifugal pump
(C) Pressure cooker (D) Bomb calorimeter
Ans: (b)
02. A thermodynamic system is considered to be an isolated one if
(A) Mains transfer and entropy change are zero
(B) Entropy change and energy transfer are zero
(C) Energy transfer and mass transfer are zero
(D) Mass transfer and volume change are zero
Ans: (c)
03. Reduced pressure is
(A) Always less than atmospheric pressure (B) Always unity
(C) An index of molecular position of a gas (D) Dimensionless
Ans: (d)
04. Match List I with List II and select the correct answer using the code given below the
lists:
List I List II
A. n = ∞
B. n = 1.4
C. n = 1.0
D. n = 0
Code : A B C D
(a) 4 3 2 1
(b) 1 3 2 4
(c) 4 2 3 1
(d) 1 2 3 4
Ans: (a)
06. A closed system is one in which
(A) Mass does not cross boundaries of the system, though energy may do so
(B) Mass crosses the boundary but not the energy
(C) Neither mass nor energy cross the boundary of the system
(D) Both energy and mass cross the boundaries of the system
Ans: (a)
07. Work transfer between the system and the surroundings
(A) Is a point function (B) Is always given by ∫ P dv
(C) Is a function of pressure only (D) Depends on the path followed by the system
Ans: (d)
08. Air is being forced by the bicycle pump into a tyre against a pressure of 4-5 bars. A slow
downward movement of the piston can be approximated as
(A) Isobaric process
(B) Adiabatic process
(C) Throttling process
(D) Isothermal process
Ans: (d)
09. Isentropic flow is
(A) Irreversible adiabatic flow (B) Reversible adiabatic flow
(C) Ideal fluid flow (D) Frictionless reversible flow
Ans: (b)
10. Increase in entropy of a system represents
(A) Increase in availability of energy (B) Increase in temperature
(C) Decrease in pressure (D) Degradation of energy
Ans: (d)
12. Lowest COP is of vapour
(A) Compression cycle with superheated vapour
(B) Compression cycle with dry compression
(C) Compression cycle with wet compression
(D) Absorption cycle
Ans: (d)
13. The cycle in which heat is supplied at constant volume and rejected at constant pressure is
known as
(A) Dual combustion cycle (B) Diesel cycle
(C) Atkinson cycle (D) Rankine cycle
Ans: (c)
14. The boundary layer separation occurs when
(A) Pressure gradient is positive (B) Pressure gradient is zero
(C) Pressure gradient is negative (D) none of the above
Ans: (a)
15. For minimum work input in a two-stage compression process the intermediate pressure is the
(A) Arithmetic mean of suction and discharge pressures
(B) Logarithmic means of suction and discharge pressures
(C) Geometric mean of suction and discharge pressures
(D) Hyperbolic mean of suction and discharge pressures
Ans: (c)
16. Air injection is IC engine refers to injection of
(A) Air only (B) Liquid fuel only (C) liquid fuel and air (D) Supercharging air
Ans: (b)
17. Supercharging is the process of
(A) Supplying the intake of an engine with air at a density greater than the density of the surrounding atmosphere
(B) Providing forced cooling air
(C) Injection of compressed air to remove combustion products fully
(D) Raising exhaust pressure
Ans: (a)
18. Turbo prop-engine has the following additional feature over the turbojet :
(A) Propeller (B) Diffuser
(C) Starting engine (D) Turbine and combustion chamber
Ans: (a)
19. In the SI engine, highest UBHC concentration is observed during
(A) Maximum load (B) Acceleration (C) Deceleration (D) Idling
Ans: (d)
21. Pistons of Diesel engines are usually cooled by
(A) Air (B) Water (C) Lubricating all (D) Fuel oil
Ans: (a)
22. When a hydrocarbon fuel burns in excess air Orsat analysis of products of combustion will show
(A) CO, CO2 and N2 (B) CO2, CO, N2 and H2O
(C) CO2, N2, O2 and H2O (D) CO2, N2 and O2
Ans: (d)
23. What will be the products of combustion shown by an Orsat analyzer when natural gas burns in deficit air ?
(A) CO2, O2 and N2 (B) CO2, CO, and N2
(C) CO2, CO, N2 and H2O (D) CO2, CO, N2 and O2
Ans: (b)
24. The energy produced by 4-5 tons of high grade coal is equivalent to the energy produced by
(A) 1 kg of Uranium (B) 1 gram of Uranium
(C) 100 grams of Uranium (D) 10 grams of Uranium
Ans: (b)
