320 Important Engineering Thermodynamics MCQ Question and Answer | PDF Free Download
1.The hard coke is obtained when carbonization of coal is carried out at
- A500° to 700°C
- B700° to 900°C
- C300° to 500°C
- D900° to 1100°C
2.In an ideal gas turbine plant, it is assumed that the compression and expansion processes are
- AIsothermal
- BIsentropic
- CPolytropic
- DNone of these
3.The value of gas constant (R) in S. I. units is
- A0.287 J/kgK
- B2.87 J/kgK
- C28.7 J/kgK
- D287 J/kgK
4.An open system is one in which
- AMass does not cross boundaries of the system, though energy may do so
- BNeither mass nor energy crosses the boundaries of the system
- CBoth energy and mass cross the boundaries of the system
- DMass crosses the boundary but not the energy
5.An isolated system is one in which
- AMass does not cross boundaries of the system, though energy may do so
- BNeither mass nor energy crosses the boundaries of the system
- CBoth energy and mass cross the boundaries of the system
- DMass crosses the boundary but not the energy
6.A closed system is one in which
- AMass does not cross boundaries of the system, though energy may do so
- BMass crosses the boundary but not the energy
- CNeither mass nor energy crosses the boundaries of the system
- DBoth energy and mass cross the boundaries of the system
7.For a perfect gas, according to Boyle’s law (where P = Absolute pressure, V = Volume and T = Absolute temperature)
- AV/T = constant, if p is kept constant
- BP v = constant, if T is kept constant
- CT/P = constant, if v is kept constant
- DP/T = constant, if v is kept constant
8.The volumetric or molar specific heat at constant pressure is the product of
- AMolecular mass of the gas and the specific heat at constant volume
- BAtomic mass of the gas and the gas constant
- CMolecular mass of the gas and the gas constant
- DNone of the above
9.The condition for the reversibility of a cycle is
- AThe pressure and temperature of the working substance must not differ, appreciably, from those of the surroundings at any stage in the process
- BAll the processes, taking place in the cycle of operation, must be extremely slow
- CThe working parts of the engine must be friction free
- DAll of the above
10.For which of the following substances, the gas laws can be used with minimum error
- ADry steam
- BWet steam
- CSaturated steam
- DSuperheated steam
11.The pressure exerted by an ideal gas is ________ of the kinetic energy of all the molecules contained in a unit volume of gas.
- AOne-third
- BThree-forth
- COne-half
- DTwo-third
12.In a Carnot cycle, heat is transferred at
- AConstant pressure
- BConstant volume
- CConstant temperature
- DConstant enthalpy
14.The heating of gas at constant volume is governed by
- ABoyle's law
- BCharles' law
- CGay-Lussac law
- DAvogadro's law
15.For the same compression ratio, the efficiency of dual combustion cycle is
- AGreater than Diesel cycle and less than Otto cycle
- BGreater than Diesel cycle
- CLess than Diesel cycle
- DLess than Diesel cycle and greater than Otto cycle
16.Which of the following gas has a minimum molecular mass?
- AOxygen
- BNitrogen
- CHydrogen
- DMethane
17.If a system after undergoing a series of processes, returns to the initial state then
- AProcess is thermodynamically in equilibrium
- BProcess is executed in closed system cycle
- CIts entropy will change due to irreversibility
- DSum of heat and work transfer will be zero
18.For reversible adiabatic process, change in entropy is
- AMaximum
- BMinimum
- CZero
- DNegative
19.When coal is first dried and then crushed to a fine powder by pulverizing machine, the resulting fuel is called
- AWood charcoal
- BBituminous coal
- CBriquetted coal
- DNone of these
20.Brayton cycle consists' of following four processes
- ATwo isothermal and two isentropic
- BTwo isentropic and two constant volumes
- CTwo isentropic, one constant volume and one constant pressure
- DTwo isentropic and two constant pressures