320 Important Engineering Thermodynamics MCQ Question and Answer | PDF Free Download
2.One kg of ethylene (C2H4) requires 2 kg of oxygen and produces 22/7 kg of carbon dioxide and __________ kg of water or steam.
- A9/7
- B11/7
- C7/4
- D11/4
3.One kg of carbon produces ________ kg of carbon dioxide.
- A3/7
- B11/7
- C11/3
- D4/11
4.The ratio of two specific heats of air is equal to
- A0.17
- B0.24
- C0.1
- D1.41
5.In a free expansion process
- AWork done is zero
- BHeat transfer is zero
- CBoth (A) and (B) above
- DWork done is zero but heat increases
6.Absolute zero pressure will occur
- AAt sea level
- BWhen molecular momentum of the system becomes zero
- CUnder vacuum conditions
- DAt a temperature of 273°K
7.The ideal efficiency of a Brayton cycle with regeneration, with increase in pressure ratio will
- AIncrease
- BDecrease
- CRemain unchanged
- DIncrease/decrease depending on application
8.When a gas is heated, change takes place in
- ATemperature
- BPressure
- CVolume
- DAll of these
9.According to Dalton's law, the total pressure of the mixture of gases is equal to
- AGreater of the partial pressures of all
- BAverage of the partial pressures of all
- CSum of the partial pressures of all
- DSum of the partial pressures of all divided by average molecular weight
10.Gases have
- AOnly one value of specific heat
- BTwo values of specific heat
- CNo value of specific heat
- DUnder some conditions one value and sometimes two values of specific heat
11.A gas is compressed in a cylinder by a movable piston to a volume one half its original volume. During the process 300 kJ heat left the gas and internal energy remained same. The work done on gas in Nm will be
- A300 Nm
- B300,000 Nm
- C30 Nm
- D3000 Nm
12.According to First law of thermodynamics,
- ATotal internal energy of a system during a process remains constant
- BTotal energy of a system remains constant
- CWork-done by a system is equal to the heat transferred by the system
- DInternal energy, enthalpy and entropy during a process remain constant
13.If a certain amount of dry ice is mixed with same amount of water at 80°C, the final temperature of mixture will be
- A80°C
- B0°C
- C40°C
- D20°C
14.The oxygen atom is ________ times heavier than the hydrogen atom.
- A2
- B8
- C16
- D32
15.One molecule of oxygen is __________ times heavier than the hydrogen atom.
- A2
- B8
- C16
- D32
16.If heat be exchanged in a reversible manner, which of the following property of the working substance will change accordingly
- ATemperature
- BEnthalpy
- CInternal energy
- DEntropy
17.A sudden fall in the barometer reading is a sign of approaching
- AFine weather
- BRains
- CStorm
- DCold wave
18.The heat and work are mutually convertible. This statement is called __________ law of thermodynamics.
- AZeroth
- BFirst
- CSecond
- DThird
19.According to Kelvin-Planck’s statement of second law of thermodynamics,
- AIt is possible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work
- BIt is impossible to construct a device which operates in a cyclic process and produces no effect other than the transfer of heat from a cold body to a hot body
- CIt is impossible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work
- DNone of the above
20.The fuel mostly used in cement industry and in metallurgical processes is
- AWood charcoal
- BBituminous coke
- CPulverized coal
- DCoke