Thermodynamics Actual Exam 2026
Complete Questions and Verified
Answers with Detailed Rationales 100%
Correct Grade A Pass Guaranteed - A+
Graded
Question 1
Which property depends only on the current state of a system and not on the
path taken to reach that state?
A. Heat
B. Work
C. Internal energy
D. Friction
Answer: C. Internal energy
Rationale: Internal energy is a thermodynamic state property. Its value depends
only on the system's present state, regardless of the process used to reach that
state. Heat and work are path functions and therefore depend on the specific
process.
Question 2
The SI unit of pressure is:
A. Joule
B. Watt
,C. Newton
D. Pascal
Answer: D. Pascal
Rationale: The pascal (Pa) is the SI unit of pressure and is equal to one newton per
square meter (N/m²).
Question 3
According to the First Law of Thermodynamics, energy can be:
A. Created but not destroyed
B. Destroyed but not created
C. Transferred or converted but neither created nor destroyed
D. Eliminated by friction
Answer: C. Transferred or converted but neither created nor destroyed
Rationale: The First Law expresses conservation of energy. Energy may change
form or move between systems, but the total amount remains constant.
Question 4
Which thermodynamic property is measured in kelvins (K)?
A. Pressure
B. Volume
C. Specific heat
D. Temperature
Answer: D. Temperature
Rationale: The kelvin is the SI base unit for thermodynamic temperature.
Question 5
A closed system is one that:
,A. Allows mass and energy to cross its boundary
B. Allows only mass to cross its boundary
C. Allows neither mass nor energy to cross its boundary
D. Allows energy but not mass to cross its boundary
Answer: D. Allows energy but not mass to cross its boundary
Rationale: A closed system exchanges energy through heat or work but does not
exchange mass with its surroundings.
Question 6
The specific volume of a substance is defined as:
A. Mass divided by pressure
B. Volume per unit mass
C. Pressure divided by density
D. Density multiplied by volume
Answer: B. Volume per unit mass
Rationale: Specific volume is the reciprocal of density and represents the volume
occupied by one unit of mass.
Question 7
Which process occurs at constant pressure?
A. Isochoric
B. Isothermal
C. Isobaric
D. Isentropic
Answer: C. Isobaric
Rationale: An isobaric process occurs while pressure remains constant throughout
the process.
, Question 8
The ideal gas law is expressed as:
A. PV = mgh
B. PV = nRT
C. P = ρgh
D. W = Fd
Answer: B. PV = nRT
Rationale: The ideal gas equation relates pressure, volume, temperature, amount
of gas, and the universal gas constant.
Question 9
Which property is an intensive property?
A. Total mass
B. Total volume
C. Total internal energy
D. Temperature
Answer: D. Temperature
Rationale: Intensive properties do not depend on the amount of substance
present. Temperature is intensive, whereas mass and volume are extensive.
Question 10
The primary purpose of a turbine is to:
A. Increase fluid pressure
B. Transfer heat into a fluid
C. Produce work from a flowing fluid
D. Condense vapor
Answer: C. Produce work from a flowing fluid
Complete Questions and Verified
Answers with Detailed Rationales 100%
Correct Grade A Pass Guaranteed - A+
Graded
Question 1
Which property depends only on the current state of a system and not on the
path taken to reach that state?
A. Heat
B. Work
C. Internal energy
D. Friction
Answer: C. Internal energy
Rationale: Internal energy is a thermodynamic state property. Its value depends
only on the system's present state, regardless of the process used to reach that
state. Heat and work are path functions and therefore depend on the specific
process.
Question 2
The SI unit of pressure is:
A. Joule
B. Watt
,C. Newton
D. Pascal
Answer: D. Pascal
Rationale: The pascal (Pa) is the SI unit of pressure and is equal to one newton per
square meter (N/m²).
Question 3
According to the First Law of Thermodynamics, energy can be:
A. Created but not destroyed
B. Destroyed but not created
C. Transferred or converted but neither created nor destroyed
D. Eliminated by friction
Answer: C. Transferred or converted but neither created nor destroyed
Rationale: The First Law expresses conservation of energy. Energy may change
form or move between systems, but the total amount remains constant.
Question 4
Which thermodynamic property is measured in kelvins (K)?
A. Pressure
B. Volume
C. Specific heat
D. Temperature
Answer: D. Temperature
Rationale: The kelvin is the SI base unit for thermodynamic temperature.
Question 5
A closed system is one that:
,A. Allows mass and energy to cross its boundary
B. Allows only mass to cross its boundary
C. Allows neither mass nor energy to cross its boundary
D. Allows energy but not mass to cross its boundary
Answer: D. Allows energy but not mass to cross its boundary
Rationale: A closed system exchanges energy through heat or work but does not
exchange mass with its surroundings.
Question 6
The specific volume of a substance is defined as:
A. Mass divided by pressure
B. Volume per unit mass
C. Pressure divided by density
D. Density multiplied by volume
Answer: B. Volume per unit mass
Rationale: Specific volume is the reciprocal of density and represents the volume
occupied by one unit of mass.
Question 7
Which process occurs at constant pressure?
A. Isochoric
B. Isothermal
C. Isobaric
D. Isentropic
Answer: C. Isobaric
Rationale: An isobaric process occurs while pressure remains constant throughout
the process.
, Question 8
The ideal gas law is expressed as:
A. PV = mgh
B. PV = nRT
C. P = ρgh
D. W = Fd
Answer: B. PV = nRT
Rationale: The ideal gas equation relates pressure, volume, temperature, amount
of gas, and the universal gas constant.
Question 9
Which property is an intensive property?
A. Total mass
B. Total volume
C. Total internal energy
D. Temperature
Answer: D. Temperature
Rationale: Intensive properties do not depend on the amount of substance
present. Temperature is intensive, whereas mass and volume are extensive.
Question 10
The primary purpose of a turbine is to:
A. Increase fluid pressure
B. Transfer heat into a fluid
C. Produce work from a flowing fluid
D. Condense vapor
Answer: C. Produce work from a flowing fluid
