MCQOPTIONS
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MCQOPTIONS
This section includes 1092 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 901. |
_Change in internal energy in a closed system is equal to heat transferred if the reversible process takes place at constant$? |
| A. | Pressure |
| B. | Temperature |
| C. | Volume |
| D. | Internal energy |
| Answer» D. Internal energy | |
| 902. |
_One kilowatt is equal to$? |
| A. | 1 N-m/s |
| B. | 100 N-m |
| C. | 1000 N-m/s |
| D. | 1 √ó 106 N-m/s |
| Answer» D. 1 ‚àö√≥ 106 N-m/s | |
| 903. |
_Second law of thermodynamics defines$? |
| A. | Heat |
| B. | Work |
| C. | Internal energy |
| D. | Entropy |
| Answer» E. | |
| 904. |
_The compression ratio is the ratio of$? |
| A. | Total volume to swept volume |
| B. | Swept volume to clearance volume |
| C. | Swept volume to total volume |
| D. | Total volume to clearance volume |
| Answer» E. | |
| 905. |
_Which of the following is a reversible non-flow process?$? |
| A. | Isochoric process |
| B. | Isobaric process |
| C. | Hyperbolic process |
| D. | All of these |
| Answer» E. | |
| 906. |
_When coal is first dried and then crushed to a fine powder by pulverizing machine, the resulting fuel is called$? |
| A. | Wood charcoal |
| B. | Bituminous coal |
| C. | Briquetted coal |
| D. | None of these |
| Answer» E. | |
| 907. |
_The efficiency of Joule cycle is$? |
| A. | Less than Carnot cycle |
| B. | Equal to Carnot cycle |
| C. | Greater than Carnot cycle |
| D. | None of these |
| Answer» B. Equal to Carnot cycle | |
| 908. |
_One reversible heat engine operates between 1600 K and T2 K and another reversible heat engine operates between T2 K and 400 K. If both the engines have the same heat input and output, then temperature T2 is equal to$? |
| A. | 800 K |
| B. | 1000 K |
| C. | 1200 K |
| D. | 1400 K |
| Answer» B. 1000 K | |
| 909. |
_The heat absorbed or rejected by the working substance is given by (where ds = Increase or decrease of entropy, T = Absolute temperature, and dQ = Heat absorbed or rejected)$? |
| A. | δQ = T.ds |
| B. | δQ = T/ds |
| C. | dQ = ds/T |
| D. | None of these |
| Answer» B. ≈í¬•Q = T/ds | |
| 910. |
_A cycle consisting of __________ and two isothermal processes is known as Stirling cycle.$? |
| A. | Two constant pressure |
| B. | Two constant volume |
| C. | Two isentropic |
| D. | One constant pressure, one constant volume |
| Answer» C. Two isentropic | |
| 911. |
_The total energy of a molecule is shared equally by the various degrees of freedom possessed by it. This law is known as$? |
| A. | Law of equipartition of energy |
| B. | Law of degradation of energy |
| C. | Law of conservation of energy |
| D. | None of these |
| Answer» B. Law of degradation of energy | |
| 912. |
_The isothermal and adiabatic processes are regarded as$? |
| A. | Reversible process |
| B. | Irreversible process |
| C. | Reversible or irreversible process |
| D. | None of these |
| Answer» B. Irreversible process | |
| 913. |
_In an extensive property of a thermodynamic system$? |
| A. | Extensive heat is transferred |
| B. | Extensive work is done |
| C. | Extensive energy is utilized |
| D. | None of these |
| Answer» E. | |
| 914. |
_Barometric pressure is equal to$? |
| A. | 760 mm Hg |
| B. | Zero mm Hg |
| C. | 735.6 mm Hg |
| D. | 1 mm Hg |
| Answer» B. Zero mm Hg | |
| 915. |
An actual engine is to be designed having same efficiency as the Carnot cycle. Such a proposition is$? |
| A. | Feasible |
| B. | Impossible |
| C. | Possible |
| D. | Possible, but with lot of sophistications |
| Answer» E. | |
| 916. |
Measurement of temperature is based on$? |
| A. | Thermodynamic properties |
| B. | Zeroth law of thermodynamics |
| C. | First law of thermodynamics |
| D. | Second law of thermodynamics |
| Answer» C. First law of thermodynamics | |
| 917. |
Producer gas is obtained by$? |
| A. | Carbonization of bituminous coal |
| B. | Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast |
| C. | Passing steam over incandescent coke |
| D. | Passing air and a large amount of steam over waste coal at about 650°C |
| Answer» C. Passing steam over incandescent coke | |
| 918. |
Which law states that the specific heat of a gas remains constant at all temperatures and pressures?$? |
| A. | Charles' Law |
| B. | Joule's Law |
| C. | Regnault's Law |
| D. | Boyle's Law |
| Answer» D. Boyle's Law | |
| 919. |
The gas turbine cycle with regenerator improves$? |
| A. | Work ratio |
| B. | Thermal efficiency |
| C. | Avoid pollution |
| D. | None of these |
| Answer» C. Avoid pollution | |
| 920. |
Select the wrong statement$? |
| 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» B. An Otto cycle consists of two constant volume and two isentropic processes. | |
| 921. |
In an isothermal process, the internal energy$? |
| A. | Increases |
| B. | Decreases |
| C. | Remain constant |
| D. | First increases and then decreases |
| Answer» D. First increases and then decreases | |
| 922. |
The entropy __________ in an irreversible cyclic process.$? |
| A. | Remains constant |
| B. | Decreases |
| C. | Increases |
| D. | None of these |
| Answer» D. None of these | |
| 923. |
If both Stirling and Carnot cycles operate within the same temperature limits, then efficiency of Stirling cycle as compared to Carnot cycle$? |
| A. | More |
| B. | Less |
| C. | Equal |
| D. | Depends on other factors |
| Answer» D. Depends on other factors | |
| 924. |
Stirling cycle consists of$? |
| A. | Two constant volume and two isentropic processes |
| B. | Two constant volume and two isothermal processes |
| C. | Two constant pressure and two isothermal processes |
| D. | One constant volume, one constant pressure and two isentropic processes |
| Answer» C. Two constant pressure and two isothermal processes | |
| 925. |
Entropy change depends on$? |
| A. | Heat transfer |
| B. | Mass transfer |
| C. | Change of temperature |
| D. | Thermodynamic state |
| Answer» B. Mass transfer | |
| 926. |
One kg of carbon requires 4/3 kg of oxygen and produces ________ kg of carbon monoxide gas.$? |
| A. | 8/3 |
| B. | 7/3 |
| C. | 11/7 |
| D. | 11/3 |
| Answer» C. 11/7 | |
| 927. |
The behavior of super-heated vapour is similar to that of$? |
| A. | Perfect gas |
| B. | Air |
| C. | Steam |
| D. | Ordinary gas |
| Answer» B. Air | |
| 928. |
Gases have$? |
| A. | Only one value of specific heat |
| B. | Two values of specific heat |
| C. | No value of specific heat |
| D. | Under some conditions one value and sometimes two values of specific heat |
| Answer» C. No value of specific heat | |
| 929. |
Work done is zero for the following process$? |
| A. | Constant volume |
| B. | Free expansion |
| C. | Throttling |
| D. | All of the above |
| Answer» E. | |
| 930. |
Universal gas constant is defined as equal to product of the molecular weight of the gas and$? |
| A. | Specific heat at constant pressure |
| B. | Specific heat at constant volume |
| C. | Ratio of two specific heats |
| D. | Gas constant |
| Answer» E. | |
| 931. |
A path 1-2-3 is given. A system absorbs 100 kJ as heat and does 60 kJ of work while along the path 1-4-3, it does 20 kJ of work. The heat absorbed during the cycle 1-4-3 is$? |
| A. | -140 kJ |
| B. | -80 kJ |
| C. | -40 kJ |
| D. | +60 kJ |
| Answer» E. | |
| 932. |
The pressure exerted by an ideal gas is ________ of the kinetic energy of all the molecules contained in a unit volume of gas.$? |
| A. | One-third |
| B. | Three-forth |
| C. | One-half |
| D. | Two-third |
| Answer» E. | |
| 933. |
The hard coke is obtained when carbonization of coal is carried out at$? |
| A. | 500° to 700°C |
| B. | 700° to 900°C |
| C. | 300° to 500°C |
| D. | 900° to 1100°C |
| Answer» E. | |
| 934. |
A closed system is one in which$? |
| 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 crosses the boundaries of the system |
| D. | Both energy and mass cross the boundaries of the system |
| Answer» B. Mass crosses the boundary but not the energy | |
| 935. |
The efficiency of Carnot cycle is maximum for$? |
| A. | Gas engine |
| B. | Petrol engine |
| C. | Steam engine |
| D. | Reversible engine |
| Answer» E. | |
| 936. |
The heat and work are mutually convertible. This statement is called __________ law of thermodynamics.$? |
| A. | Zeroth |
| B. | First |
| C. | Second |
| D. | Third |
| Answer» C. Second | |
| 937. |
The air standard efficiency of an Otto cycle is given by (where r = Compression ratio, and γ = Ratio of specific heats)$? |
| A. | 1 - rγ - 1 |
| B. | 1 + rγ - 1 |
| C. | 1 - (1/ rγ - 1) |
| D. | 1 + (1/ rγ - 1) |
| Answer» D. 1 + (1/ r≈í‚â• - 1) | |
| 938. |
When a gas is heated at constant volume$? |
| A. | Its temperature will increase |
| B. | Its pressure will increase |
| C. | Both temperature and pressure will increase |
| D. | Neither temperature nor pressure will increase |
| Answer» D. Neither temperature nor pressure will increase | |
| 939. |
The following cycle is used for air craft refrigeration$? |
| A. | Brayton cycle |
| B. | Joule cycle |
| C. | Carnot cycle |
| D. | Reversed Brayton cycle |
| Answer» E. | |
| 940. |
The thermal efficiency of an ideal gas turbine plant is given by (where r = Pressure ratio)$? |
| A. | rγ - 1 |
| B. | 1 - rγ - 1 |
| C. | 1 - (1/r) γ/γ - 1 |
| D. | 1 - (1/r) γ - 1/ γ |
| Answer» E. | |
| 941. |
When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.$? |
| A. | Atomization |
| B. | Carbonization |
| C. | Combustion |
| D. | None of these |
| Answer» C. Combustion | |
| 942. |
The efficiency of Stirling cycle is __________ Carnot cycle.$? |
| A. | Greater than |
| B. | Less than |
| C. | Equal to |
| D. | None of these |
| Answer» D. None of these | |
| 943. |
If a gas is heated against a pressure, keeping the volume constant, then work done will be equal to$? |
| A. | +ve |
| B. | -ve |
| C. | Zero |
| D. | Anywhere between zero and infinity |
| Answer» D. Anywhere between zero and infinity | |
| 944. |
The smallest quantity of a substance, which can exist by itself in a chemically recognizable form is known as$? |
| A. | Element |
| B. | Compound |
| C. | Atom |
| D. | Molecule |
| Answer» E. | |
| 945. |
During which of the following process does heat rejection takes place in Carnot cycle?$? |
| A. | Isothermal expansion |
| B. | Isentropic expansion |
| C. | Isothermal compression |
| D. | Isentropic compression |
| Answer» D. Isentropic compression | |
| 946. |
The unit of time in S.I. units is$? |
| A. | Second |
| B. | Minute |
| C. | Hour |
| D. | Day |
| Answer» B. Minute | |
| 947. |
Total heat of a substance is also known as$? |
| A. | Internal energy |
| B. | Entropy |
| C. | Thermal capacity |
| D. | Enthalpy |
| Answer» E. | |
| 948. |
The amount of heat required to raise the temperature of 1 kg of water through one Kelvin is called$? |
| A. | Specific heat at constant volume |
| B. | Specific heat at constant pressure |
| C. | kilo-Joule |
| D. | None of these |
| Answer» D. None of these | |
| 949. |
Water contained in a beaker can be made to boil by passing steam through it$? |
| A. | At atmospheric pressure |
| B. | At a pressure greater than atmospheric pressure |
| C. | Any pressure |
| D. | Not possible |
| Answer» C. Any pressure | |
| 950. |
Mixture of ice and water form a$? |
| A. | Closed system |
| B. | Open system |
| C. | Isolated system |
| D. | Heterogeneous system |
| Answer» E. | |