থার্মোডায়নামিক্স অ্যান্ড হিট ইঞ্জিনস MCQ
1. For the same heat input and same compression ration.
Otto cycle and diesel cycle are equally efficient
Otto cycle is less efficient than diesel cycle
Efficiency depends mainly on working substance
None of the above
2. A process in which the temperature of the working substance remains constant during its expansion or compression is called-
Isothermal process
Hyperbolic process
Adiabatic process
Polytrophic process
3. The entropy in an irreversible cyclic process is -
Remains constant
Decrease
Increase
None of them
4. In an isolated system, can be transferred between the system and its surrounding.
Only energy
Only mass
Both energy and mass
Neither energy nor mass
5. A heat exchange process in which the product of pressure and volume Remains constant is known as-
Heat exchange process
Throttling process
Isentropic process
Hyperbolic process
6. An ideal gas as compared to a real gas at very high pressure occupies-
More volume
Less volume
Same volume
Unpredictable behaviour
7. The same volume of all gases would represent their-
Densities
Specific weights
Molecular weights
Gas characteristic constants
8. If a gas vapour is allowed to expand through a very minute aperture, then such a process is known as-
Free expansion
Hyperbolic expansion
Adiabatic expansion
Throttling
9. A mixture of gas expands from 0.03m to 0.06^3m at a constant pressure of 1 mpa and absorbs 84kj of heat during the process. The change in internal energy of the mixture is-
30 kj
54 kj
84 kj
114 kj
10. An isolated system is one in which-
Mass does not cross boundaries of the system, though energy may do so
Neither mass nor energy crosses the boundaries of the system
Both energy and mass cross the boundaries of the system
Mass crosses the boundary but not the energy
11. To convert volumetric analysis to gravimetric analysis, the relative volume of each constituent of the flue gases is-
Divided by its molecular weight
Multiplied by its molecular weight
Multiplied by its density
Multiplied by its specific weight
12. Which of the following parameters is constant for a mole for most of the gases at a given temperature and pressure?
Enthalpy
Volume
Mass
Entropy
13. The ratio of specific heat at constant pressure (Cp) and specific heat at constant volume (Cv) is-
Equal to one
Less than one
Greater than one
None
14. The extensive properties of a system,-
Are independent of the mass of the system
Depend upon temperature of the system
Depend upon the mass of the system
None of the above
15. The value of n = 1 in the polytropic process indicates it to be-
Reversible process
Isothermal process
Adiabatic process
Irreversible process
16. Which of the following is an extensive property?
Volume
Pressure
Viscosity
All of the above
17. Work done in an adiabatic process between a given pair of end states depends on-
The end states only
particular adiabatic process
The value of index n
The value of heatt ransferred
18. The specific heat of air increases with increase in-
Temperature
Pressure
Both pressure and temperature
Variation of its constituents
19. When a gas is heated change takes place in.
Pressure
Volume
Temperature
All of these
20. Change in enthalpy of a system is the heat supplied at-
Constant pressure
Constant temperature
Constant volume
Constant entropy