MCQOPTIONS
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MCQOPTIONS
This section includes 189 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The molecular mass of a substance is the number of times a molecule of that substance is heavier than the hydrogen atom. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 2. |
The behaviour of super-heated vapour is similar to that of |
| A. | perfect gas |
| B. | air |
| C. | steam |
| D. | ordinary gas |
| Answer» B. air | |
| 3. |
Briquetted coal is produced from the finely ground coal by moulding under pressure with or without a binding material. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 4. |
Which of the following is a reversible non-flow process? |
| A. | Isochoric process |
| B. | Isobaric process |
| C. | Hyperbolic process |
| D. | all of these |
| Answer» E. | |
| 5. |
If in the equation = , the value of = ∝ , then the process is called |
| A. | constant volume process |
| B. | adiabatic process |
| C. | constant pressure process |
| D. | isothermal process |
| Answer» B. adiabatic process | |
| 6. |
A close cycle gas turbine gives __________ efficiency as compared to an open cycle gas turbine. |
| A. | same |
| B. | lower |
| C. | higher |
| Answer» D. | |
| 7. |
Charles' law states that all perfect gases change in volume by __________ of its original volume at 0° C for every 1° C change in temperature, when pressure remains constant. |
| A. | 1/27th |
| B. | 1/93th |
| C. | 1/173th |
| D. | 1/273th |
| Answer» E. | |
| 8. |
The throttling process is an irreversible steady flow expansion process. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 9. |
The efficiency of the dual combustion cycle for the same compression ratio, is __________ Diesel cycle. |
| A. | greater than |
| B. | less than |
| C. | equal to |
| Answer» B. less than | |
| 10. |
The amount of heat generated per kg of fuel is known as |
| A. | calorific value |
| B. | heat energy |
| C. | lower calorific value |
| D. | higher calorific value |
| Answer» B. heat energy | |
| 11. |
Carnot cycle has maximum efficiency for |
| A. | petrol engine |
| B. | diesel engine |
| C. | reversible engine |
| D. | irreversible engine |
| Answer» D. irreversible engine | |
| 12. |
It is __________ to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work. |
| A. | possible |
| B. | impossible |
| Answer» C. | |
| 13. |
The thermal efficiency of an ideal gas turbine plant is given by (where = Pressure ratio) |
| A. | 1 - |
| Answer» E. | |
| 14. |
To ensure complete and rapid combustion of a fuel, some quantity of air, in excess of the theoretical or minimum air is supplied. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 15. |
According to Regnault's law, the specific heat at constant pressure () and specific heat at constant volume () __________ with the change in pressure and temperature of the gas. |
| A. | change |
| B. | do not change |
| Answer» C. | |
| 16. |
One molecule of oxygen is __________ times heavier than the hydrogen atom. |
| A. | 12 |
| B. | 14 |
| C. | 16 |
| D. | 32 |
| Answer» E. | |
| 17. |
Relation between and is given by (where = Specific heat at constant pressure, = Specific heat at constant volume, γ = /, known as adiabatic index, and = Gas constant) |
| A. | - |
| B. | = |
| C. | Both (B) and (C) |
| Answer» E. | |
| 18. |
The elements are made up of minute and chemically invisible particles as atoms. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 19. |
All perfect gases change in volume by 1 / 273th of its original volume at 0°C for every 1°C change in temperature, when the pressure remains constant. This statement is called |
| A. | Boyle's law |
| B. | Charles' law |
| C. | Gay-Lussac law |
| D. | Joule's law |
| Answer» C. Gay-Lussac law | |
| 20. |
A good fuel should have __________ ignition point. |
| A. | high |
| B. | low |
| Answer» C. | |
| 21. |
The property of the system, whose value for the entire system is equal to the sum of their values for the individual parts of the system is called extensive property |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 22. |
Coal gas consists mainly of hydrogen, carbon monoxide and various hydrocarbons. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 23. |
When the finely ground coal is moulded under pressure with or without a binding material, the resulting fuel is called briquetted coal. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 24. |
The heat and work are mutually convertible. This statement is called __________ law of thermodynamics. |
| A. | Zeroth |
| B. | First |
| C. | Second |
| Answer» C. Second | |
| 25. |
The amount of heat obtained by the complete combustion of 1 kg of a fuel when the products of its combustion are cooled down to the temperature of supplied air is called __________ calorific value offuel. |
| A. | higher |
| B. | lower |
| Answer» B. lower | |
| 26. |
The mass of flue gas per kg of fuel is the ratio of the |
| A. | mass of oxygen in 1 kg of flue gas to the mass of oxygen in 1 kg of fuel |
| B. | mass of oxygen in 1 kg of fuel to the mass of oxygen in 1 kg of flue gas |
| C. | mass of carbon in 1 kg of flue gas to the mass of carbon in 1 kg of fuel |
| D. | mass of carbon in 1 kg of fuel to the mass of carbon in 1 kg of flue gas |
| Answer» D. mass of carbon in 1 kg of fuel to the mass of carbon in 1 kg of flue gas | |
| 27. |
Equal volumes of all gases, at the same temperature and pressure, contain equal number of molecules. This statement is called Avogadro's law. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 28. |
Wood charcoal is produced by heating the wood at 100°C. |
| A. | Yes |
| B. | No |
| Answer» C. | |
| 29. |
The __________ is obtained when carbonisation of coal is carried out at 500° to 700° C. |
| A. | soft coke |
| B. | hard coke |
| C. | pulverised coal |
| D. | bituminous coal |
| Answer» B. hard coke | |
| 30. |
The bomb calorimeter is used for finding the __________ calorific value of solid and liquid fuels. |
| A. | higher |
| B. | lower |
| Answer» B. lower | |
| 31. |
The efficiency of the Carnot cycle may be increased by |
| A. | increasing the highest temperature |
| B. | decreasing the highest temperature |
| C. | increasing the lowest temperature |
| D. | keeping the lowest temperature constant |
| Answer» B. decreasing the highest temperature | |
| 32. |
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 |
| C. | adiabatic process |
| D. | polytropic process |
| Answer» C. adiabatic process | |
| 33. |
Which of the following statement is correct according to Clausis statement of second law off thermodynamics? |
| A. | It is possible to transfer heat from a body at a lower temperature to a body at a higher temperature. |
| B. | It is impossible to transfer heat from a body at a lower temperature to a body at a higher temperature, without the aid of an external source. |
| C. | It is possible to transfer heat from a body at a lower temperature to a body at a higher temperature by using refrigeration cycle. |
| D. | none of the above |
| Answer» C. It is possible to transfer heat from a body at a lower temperature to a body at a higher temperature by using refrigeration cycle. | |
| 34. |
When coal is first dried and then crushed to a fine powder by pulverising machine, the resulting fuel is called |
| A. | wood charcoal |
| B. | bituminous coal |
| C. | briquetted coal |
| D. | none of these |
| Answer» E. | |
| 35. |
The process is adiabatic, if the value of n in the equation = , is |
| A. | 0 |
| B. | 1 |
| C. | γ |
| D. | ∝ |
| Answer» D. ∝ | |
| 36. |
The atomic mass of sulphur is |
| A. | 12 |
| B. | 14 |
| C. | 16 |
| D. | 32 |
| Answer» E. | |
| 37. |
The atomic mass of an element is the number of times the atom of that element is heavier than the hydrogen atom. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 38. |
The entropy of the universe is continually on the increase. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 39. |
The unit of energy is S. I. units is |
| A. | Joule (J) |
| B. | Joule metre (Jm) |
| C. | Watt(W) |
| D. | Joule/metre (J/m) |
| Answer» B. Joule metre (Jm) | |
| 40. |
Which of the following gas has the highest calorific value? |
| A. | Coal gas |
| B. | Producer gas |
| C. | Mond gas |
| D. | Blast furnace gas |
| Answer» B. Producer gas | |
| 41. |
The oxygen atom is __________ times heavier than the hydrogen atom. |
| A. | 2 |
| B. | 4 |
| C. | 8 |
| D. | 16 |
| Answer» E. | |
| 42. |
The efficiency of Diesel cycle depends upon |
| A. | temperature limits |
| B. | pressure ratio |
| C. | compression ratio |
| D. | cut-off ratio and compression ratio |
| Answer» E. | |
| 43. |
The total energy of a molecule is shared equally by the various degrees of freedom possessed by it. This law is known as |
| A. | law of equipartition of energy |
| B. | law of conservation of energy |
| C. | law of degradation of energy |
| D. | none of these |
| Answer» B. law of conservation of energy | |
| 44. |
The thermodynamic property of a system is said to be an intensive property whose value for the entire system __________ the sum of their value for the individual parts of the system. |
| A. | is equal to |
| B. | is not equal to |
| Answer» C. | |
| 45. |
The absolute pressure of a given mass of a perfect gas varies inversely as its volume, when the temperature remains constant. This statement is known as Charles' law. |
| A. | Yes |
| B. | No |
| Answer» C. | |
| 46. |
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» C. equal to Carnot cycle | |
| 47. |
Hydrogen is the __________ substance. |
| A. | lightest |
| B. | heaviest |
| Answer» B. heaviest | |
| 48. |
Otto cycle is also known as |
| A. | constant pressure cycle |
| B. | constant volume cycle |
| C. | constant temperature cycle |
| D. | constant temperature and pressure cycle |
| Answer» C. constant temperature cycle | |
| 49. |
The efficiency of a dual combustion cycle __________ upon cut-off ratio. |
| A. | depends |
| B. | does not depend |
| Answer» B. does not depend | |
| 50. |
The hyperbolic pocess is governed by |
| A. | Boyle's law |
| B. | Charles' law |
| C. | Gay-Lussac law |
| D. | Avogadro's law |
| Answer» B. Charles' law | |