Top 350+ Solved Thermodynamics MCQ Questions Answer
Q. The rate of discharge through the nozzle
a. remains same
b. decreases
c. increases
d. None of the above
Q. A wall 50 mm thick (thermal conductivity k = 40 W/m?C) has temperature difference on two surfaces of 100?C. What could probably change if the temperature difference of this wall drops to 100?C
a. Thickness of wall reduces to 5 mm
b. Thickness of wall increases to 500 mm
c. Thermal conductivity changes to 400 W/?C
d. Rate of heat flow drops to one tenth of the original
e. Area of heat transfer increases 10 times
Q. The specific heat at constant volume of solids obeys Deby's T3 law
a. at low pressures
b. at low temperatures
c. at high pressures
d. at all temperatures
e. Pulsejet
Q. The temperature, in degrees celsius, at which the colsius scale reading is numerically half the Fahrenheit scale reading is
a. 80?C
b. Pulsejet
c. 42?C
d. 160?C
e. 20?C
Q. A jar contains a mixture of oxygen and hydrogen gas in the ratio 1 : 5. The ratio of mean knetic energies of hydrogen and oxygen molecules is
a. Pulsejet
b. 1 ; 4
c. 1 ; 1
d. 1 ; 16
e. 1 ; 5
Q. For any irreversible process the net entropy change is
a. Zero
b. Negative
c. Positive
d. Infinite
e. Unity
Q. "Heat can flow from cold substance to hot substance with the aid of external work". Which of the following name is associated with the above statement?
a. Gay Lussac
b. Clausius
c. Planck
d. Kelvin
e. Joule
Q. In which case the work done per kg of air compressed from 1.05 ata, 15?C to 6.3 ata is minimum
a. Polytropic pv1.4 = C
b. Adiabatic
c. Isothermal
d. Polytropic pv1.3 = C
e. Polytropic pv1.35 = C
Q. The statement that molecular weight of all gases occupy the same volume at NTP is known as
a. Dalton's law
b. Avogadro's hypothesis
c. Joule's law
d. First law of thermodynamics
e. Charle's law
Q. 1 atmospheric pressure is equal to
a. 1.1 kg/cm2
b. 1.033 kg/cm2
c. 14.7 kg/cm2
d. 1 kg/cm2
e. 1.133 kg/cm2
Q. The relation of the vapour pressure to the enthalpy of vaporization is expressed in
a. Clausius Clapeyron equation
b. Gas equation
c. Energy equation
d. Maxwell's equation
e. Van der Waal's equation
Q. During throttling process
a. Pressure does not change
b. Entropy does not change
c. Enthalpy does not change
d. Internal energy does not change
e. Volume change is negligible
Q. Which of the following is an extensive property?
a. Pulsejet
b. Viscosity
c. Surface tension
d. Refractive index
e. Heat capacity
Q. The charge in a Diesel engine consists of
a. Air + diesel + lubricating oil
b. Diesel + lubricating oil
c. Air + lubricating oil
d. Air
e. Air + diesel
Q. Which of the following is incorrect?
a. The pressure of a mixture of gases is equal to the sum of the pressure of the individual components taken each at the temperature and volume of the mixture
b. The entropy of a mixture of gases is equal to the sum of the entropies of the individual components taken each at the temperature and volume of the mixture
c. The internal energy of a mixture of gases is equal to the sum f the internal energies of the indicudual components taken each at the temperature and the volume of the mixture
d. (B) and (C) above
e. None of the above