Top 350+ Solved Thermodynamics MCQ Questions Answer
Q. A system
a. Is a specified region, not necessarily of constant volume, where transfer of energy and/or mass are to be studied
b. Is a region of constant mass and only energy is allowed to cross the boundaries
c. Cannot transfer either energy or mass to or from the surroundings
d. Has a mass transfer across its boundaries and the mass within the system is not constant
e. None of the above
Q. An isentropic process is always
a. Irreversible and adiabatic
b. Reversible and isothermal
c. Frictionless and irreversible
d. Reversible and adiabatic
e. None of the above
Q. In a reversible polytropic process
a. The entropy remains constant
b. Some heat transfer occurs
c. The internal energy remains constant
d. The temperature remains constant
e. The ethalpy remains constant
Q. A gas which obeys kinetic theory perfectly is known as
a. Monoatomic gas
b. Perfect gas
c. Diatomic gas
d. Real gas
e. Pure gas
Q. An automobile heats up while lying in a parking 10 ton a sunny day. The process can be assumed to be
a. isothermal
b. isometric
c. isobaric
d. Pulsejet
e. isentropic
Q. The efficiency of a Carnot engine is given as 0.75. If the cycle direction is reversed, what will be the value of COP of reversed Carnot cycle
a. 0.33
b. 0.25
c. 1.33
d. 0.75
e. 4
Q. Which rays have the least wavelength?
a. Infra-red
b. Ultraviolet
c. Radio
d. Cosmic rays
e. X-rays
Q. The difference between two specific heats of a gas is equal to universal gas constant
a. When 1 gm molecule heated
b. When 1 molecule of gas is heated
c. When 1 gm molecule heated
d. When 1 gm of gas is heated
e. When any amount of gas is heated
Q. In centrifugal compressors, the ratio of outlet whirl velocity to blade velocity at outlet is known as
a. Feedback factor
b. Slip factor
c. Reheat factor
d. Gauge factor
e. Velocity factor
Q. In case of centrifugal compressors the phenomenon of unsteady, periodic and reversed flow is known as
a. Surging
b. Stalling
c. Choking
d. Either of above
e. None of the above
Q. A Rankine cycle working with saturated steam differs thermodynamically from a Carnot cycle only in the fact that
a. The Carnot cycle cannot be used for vapour
b. Steam is not the working substance for Carnot cycle
c. There are more than two sources of heat in Rankine cycle
d. Heat is supplied to the water at temperatures below the maximum temperature of the cycle
e. None of the above
Q. In case of ideal triatomic gas, the ratio of specific heats Cp/Cv would be
a. 1
b. 1.33
c. 1.4
d. 1.41
e. 1.67
Q. During adiabatic expansion which of the following remains constant
a. Internal energy
b. Temperature
c. Entropy
d. None of the above
e. Pulsejet