Explore topic-wise MCQs in Thermodynamics.

This section includes 11 Mcqs, each offering curated multiple-choice questions to sharpen your Thermodynamics knowledge and support exam preparation. Choose a topic below to get started.

1.

For proper utilization of exergy, it is desirable to make first law efficiency ____ and the source and use temperatures should ____

A. as close to unity, be different
B. as close to unity, match
C. as close to zero, match
D. as close to zero, be different
Answer» C. as close to zero, match
Discussion
2.

Both first law efficiency and second law efficiency indicate how effectively the input has been converted into the product.

A. true
B. false
Answer» B. false
Discussion
3.

In case of a heat pump, second law efficiency is given asa) (first law efficiency)*(1-Ta/To)b) (first law efficiency)*(1+To/Ta)c) (first law efficiency)*(1-To/T

A. (first law efficiency)*(1-Ta/To)
B. (first law efficiency)*(1+To/Ta)
C. (first law efficiency)*(1-To/Ta)
D. none of the mentioned
Answer» D. none of the mentioned
Discussion
4.

If solar energy Qr is available at a reservoir storage temperature of Tr and if quantity of heat Qa is transferred by the solar collector at temperature Ta, then which of the following is true?a) first law efficiency = Qa/Qrb) second law efficiency = exergy output / exergy inputc) second law efficiency = (first law efficiency)*(1-To/T

A. first law efficiency = Qa/Qr
B. second law efficiency = exergy output / exergy input
C. second law efficiency = (first law efficiency)*(1-To/Ta)/(1-To/Tr)
D. all of the mentioned
Answer» E.
Discussion
5.

If work is involved, Amin= ____ and if heat is involved, Amin= ____

A. w, Q(1+To/T)
B. W, Q(1-To/T)
C. Q(1+To/T), W
D. Q(1-To/T), W
Answer» C. Q(1+To/T), W
Discussion
6.

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
Answer» E.
Discussion
7.

For a power plant, second law efficiency can be given by desired output(W) / available energy(Wmax).

A. true
B. false
Answer» B. false
Discussion
8.

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
Answer» C. actual exergy intake / maximum exergy intake
Discussion
9.

With the concept of exergy available, which of the following is possible?

A. to analyse means of minimizing the consumption of available energy to perform a given process
B. to ensure most efficient possible conversion of energy
C. both of the mentioned
D. none of the mentioned
Answer» D. none of the mentioned
Discussion
10.

Which of the following statement is true about the first law?

A. it is concerned only with the quantities of energy
B. it disregards the form in which the energy exists
C. it does not discriminate between the energies available at different temperatures
D. all of the mentioned
Answer» E.
Discussion
11.

The first law efficiency is defined as the ratio of the output energy to the input energy.

A. true
B. false
Answer» B. false
Discussion