Top 350+ Solved Thermodynamics MCQ Questions Answer
Q. A fusible plug is utilised when
a. Impurities in water are excessive
b. Water level is too low
c. Water level is too high
d. Firing rate is high
e. Steam generation rate is high
Q. A carnot cycle engine operating between temperature range of 50?C and 100?C will have the efficiency of nearly
a. 50%
b. 26.80%
c. 13.40%
d. Pulsejet
e. 40%
Q. Free piston engines find application in
a. Compression air supply
b. Mining installation
c. Gas turbines
d. supercharging reciprocating engines
e. None of the above
Q. For a pure substance at its triple point, the number of degrees of freedom is
a. 0
b. 1
c. 2
d. None of the above
e. Pulsejet
Q. A control volume refers to
a. An isolated system
b. A specified mass
c. A fixed region in space
d. A closed system
e. A reversible process only
Q. In an adiabatic change the system
a. Heat taken from surroundings is exactly equal to heat rejected to surroundings
b. Exchanges no heat with the surroundings
c. Gives heat to the surrounding
d. Partly takes heat and partly leaves to the surroundings
e. Takes heat from the surroundings
Q. In case of axial flow compressors for minimum fluid driction and blade tip clearance losses, the blades of an axial flow compressor are disigned for
a. 53% reaction
b. 90% reaction
c. 60% reaction
d. Less than 50% reaction
e. 75% reaction
Q. If the temperature of the source is increased, the efficiency of the Carnot engine
a. Will be equal to the efficiency of a practical engine
b. Increases
c. Does not change
d. Depends on their factors
e. Decreases
Q. In Porous plug experiment the change in temperature of a gas depends upon
a. its molecular weight
b. its specific heat
c. pressure gradient on either side
d. All of the above
e. Pulsejet
Q. "What two dissimilar metals are heated at one end cooled at the other c.m.f. is developed proportional to difference of temperatures at two ends". Which of the following name is associated with the above statement?
a. Euler
b. Peltier-Thomson
c. Gay-Lussac
d. Faraday
e. Kelvin-planck
Q. Which two cycles have one constant volume, one constant pressure and two adiabatic processes each?
a. Brayton and Joules cycle
b. Diesel and Dual cycles
c. Otto and Carnot cycles
d. Sterling and Diesel cycles
e. Pulsejet
Q. If the door of a refrigerator in a room is left open, the temperature of the room will
a. decrease
b. Pulsejet
c. remain unaltered
d. increase
Q. For the same heat inpur and same compression ratio
a. Otto cycle and Diesel cycle are equally efficient
b. Otto cycle is less efficient than diesel cycle
c. Efficiency depends mainly on working substance
d. None of the above
e. Rankine
Q. In case of six stage compression of air for minimum work conditions
a. Pressure rise per stage will be equal
b. Cylinder volumes will be identical
c. Temperature rise in the cylinders will be the same
d. Work done in successive stages will be in geometrical progression
e. Piston diameters will be identical
Q. The value of characteristic gas constant in kg metre per kg per deg C as
a. 29.97
b. 1554
c. 848
d. 96
e. 53.3