# Mechanical Engineering Thermodynamics – Set 22

Are you guys looking for Mechanical Engineering MCQ Questions with Answers PDF Free Download as per Mechanical Engineering new exam pattern? You came to the right page. This may assist you to understand and check your knowledge about the Subjects. Students also can take a free test of the Multiple Choice Questions of Mechanical Engineering. Each question has four options followed by the right answer. These Mechanical Engineering MCQ Questions are selected supported by the newest exam pattern.

## Q1. A process, in which the gas is heated or expanded in such a way that the product of its pressure and volume remains constant, is called

(A) Isothermal process
(B) Hyperbolic process
(D) Polytropic process

(A) Oxygen
(B) Sulphur
(C) Nitrogen
(D) Carbon

## Q3. Which of the following gas is mostly used in town for street and domestic lighting and heating?

(A) Producer gas
(B) Coal gas
(C) Mond gas
(D) Coke oven gas

## Q4. The entropy may be expressed as a function of

(A) Pressure and temperature
(B) Temperature and volume
(C) Heat and work
(D) All of these

## Q5. Select the wrong statement

(A) A Joule cycle consists of two constant volume and two isentropic processes.
(B) An Otto cycle consists of two constant volume and two isentropic processes.
(C) An Ericsson cycle consists of two constant pressure and two isothermal processes.
(D) All of the above

Answer: (A) A Joule cycle consists of two constant volume and two isentropic processes.

(A) Volume
(B) Temperature
(C) Mass
(D) Energy

## Q7. When coal is first dried and then crushed to a fine powder by pulverizing machine, the resulting fuel is called

(A) Wood charcoal
(B) Bituminous coal
(C) Briquetted coal
(D) None of these

## Q8. The efficiency of Joule cycle is

(A) Greater than Carnot cycle
(B) Less than Carnot cycle
(C) Equal to Carnot cycle
(D) None of these

Answer: (B) Less than Carnot cycle

## Q9. In an isothermal process,

(A) There is no change in temperature
(B) There is no change in enthalpy
(C) There is no change in internal energy
(D) All of these

## Q10. The heating of a gas at constant pressure is governed by

(A) Boyle’s law
(B) Charles’ law
(C) Gay-Lussac law

## Q11. According to Avogadro’s law

(A) The product of the gas constant and the molecular mass of an ideal gas is constant
(B) The sum of partial pressure of the mixture of two gases is sum of the two
(C) Equal volumes of all gases, at the same temperature and pressure, contain equal number of molecules
(D) All of the above

Answer: (C) Equal volumes of all gases, at the same temperature and pressure, contain equal number of molecules

## Q12. The air standard efficiency of an Otto cycle is given by (where r = Compression ratio, and γ = Ratio of specific heats)

(A) 1 – rγ – 1
(B) 1 + rγ – 1
(C) 1 – (1/ rγ – 1)
(D) 1 + (1/ rγ – 1)

Answer:(C) 1 – (1/ rγ – 1)

(A) Perfect gas
(B) Air
(C) Steam
(D) Ordinary gas

(A) 9/7
(B) 11/7
(C) 7/4
(D) 11/4

## Q15. The efficiency of the dual combustion cycle for the same compression ratio is __ Diesel cycle.

(A) Greater than
(B) Less than
(C) Equal to
(D) None of these

## Q16. The mass of carbon per kg of flue gas is given by

(A) (11/3) CO2 + (3/7) CO
(B) (3/7) CO2 + (11/3) CO
(C) (7/3) CO2 + (3/11) CO
(D) (3/11) CO2 + (7/3) CO

Answer:(A) (11/3) CO2 + (3/7) CO

## Q17. In an irreversible process, there is a

(A) Loss of heat
(B) No loss of heat
(C) Gain of heat
(D) No gain of heat

(A) Sum
(B) Difference
(C) Product
(D) Ratio

## Q19. The compression ratio is the ratio of

(A) Swept volume to total volume
(B) Total volume to swept volume
(C) Swept volume to clearance volume
(D) Total volume to clearance volume

Answer: (D) Total volume to clearance volume

## Q20. In an extensive property of a thermodynamic system

(A) Extensive heat is transferred
(B) Extensive work is done
(C) Extensive energy is utilized
(D) None of these