Top 250+ Solved Engineering Thermodynamics MCQ Questions Answer
Q. Irreversibility of a process may be due to
a. lack of equilibrium during the process
b. involvement of dissipative effects
c. both of the mentioned
d. none of the mentioned
Q. All actual heat transfer processes are
a. irreversible
b. take place through a finite temperature difference
c. both of the mentioned
d. none of the mentioned
Q. At a pressure below the triple point line,
a. the substance cannot exist in the liquid phase
b. the substance when heated transforms from solid to vapour
c. both of the mentioned
d. none of the mentioned
Q. Which of the following statement is true?
a. to the left of saturated solid line is the solid region
b. between saturated solid line and saturated liquid line with respect to solidification there exists the solid-liquid mixture region
c. between two saturated liquid lines is the compressed liquid region
d. all of the mentioned
Q. The greater the temperature, the is the vapour pressure.
a. lower
b. higher
c. depends on the substance
d. none of the mentioned
Q. Phase change occurs at
a. constant pressure
b. constant temperature
c. constant pressure and temperature
d. none of the mentioned
Q. Which of the following statement is true?
a. saturation temperature is a function of pressure
b. saturation pressure is a function of temperature
c. both of the mentioned
d. none of the mentioned
Q. Example of reversed heat engine is
a. heat pump
b. refrigerator
c. both of the mentioned
d. none of the mentioned
Q. Efficiency of a reversible heat engine is given by
a. 1-(t1/t2)
b. 1-(t2/t1)
c. (t1/t2)-1
d. (t2/t1)-1
Q. For a reversible refrigerator, Coefficient of Performance is given by
a. t2/(t1-t2)
b. t1/(t1-t2)
c. t2/(t2-t1)
d. t1/(t2-t1)
Q. In an open system, there is a transfer of which of the following quantity?
a. mass
b. energy
c. entropy
d. all of the mentioned
Q. A chip dissipates 2 kJ of electric work and rejects it as heat transfer from its surface which is at 50°C to 25°C air. How much entropy is generated in the chip?
a. 4.19 j/k
b. 5.19 j/k
c. 6.19 j/k
d. 7.19 j/k
Q. Second law efficiency can also be given as
a. 1 / ( first law efficiency * carnot efficiency)
b. carnot efficiency * first law efficiency
c. carnot efficiency / first law efficiency
d. first law efficiency / carnot efficiency
Q. Second law efficiency is defined as
a. actual exergy intake / minimum exergy intake
b. minimum exergy intake / actual exergy intake
c. actual exergy intake / maximum exergy intake
d. maximum exergy intake / minimum exergy intake