# Entropy Principle - MCQs with Answers

Q1. What is the entropy change (dSiso) of a reversible isolated (dQ=0) process?

a. dSiso = 0
b. dSiso > 0
c. dSiso < 0
d. none of the above

Q2. What is the entropy change (dSiso) of a irreversible isolated (dQ=0) process?

a. dSiso = 0
b. dSiso > 0
c. dSiso < 0
d. none of the above

Q3. Which condition is correct according to the entropy principle?

a. the entropy of an isolated system can never decreases
b. the entropy of a system remains constant only when the process is reversible
c. the entropy of a system increases when the process is irreversible
d. all of the above

ANSWER: d. all of the above

Q4. What is a measure of extent of irreversibility of a process undergone by a system?

a. The entropy increase of an isolated system
b. The entropy decrease of an isolated system
c. both a. and b.
d. none of the above

ANSWER: a. The entropy increase of an isolated system

Q5. The total energy of the universe

a. is always increasing
b. is always decreasing
c. either increases or decreases
d. is always constant

Q6. At the equilibrium state of any system

a. entropy of the system becomes maximum
b. entropy of the system becomes minimum
c. entropy of the system becomes equal to entropy of the surrounding
d. none of the above

ANSWER: a. entropy of the system becomes maximum

Q7. Suppose the entropy of a system increases with increase in some parameter x. What will be the effect on entropy at equilibrium state of the system, when the parameter will be decreased?

a. the entropy decrease
b. the entropy increase
c. the entropy remains constant
d. Condition is wrong, entropy does not change with any parameter.