- Amal Augustine
- January 6, 2026
Ultimate Guide to Thermodynamics Laws MCQs to Score Better in NEET,JEE & CUET
Thermodynamics Laws MCQs form one of the most fundamental pillars of physics, governing the behavior of heat, energy, and work in all physical systems. Thermodynamics Laws MCQs are designed to test a student’s conceptual understanding of these universal principles and their application across a wide range of physical processes. From simple heat exchange problems to complex energy transformations in engines, refrigerators, and natural phenomena, thermodynamics plays a central role in explaining how energy flows and transforms in nature.
Multiple-choice questions on thermodynamics laws mcqs typically cover the Zeroth, First, Second, and Third Laws of Thermodynamics, each addressing a distinct aspect of thermal behavior. The Zeroth Law introduces the concept of thermal equilibrium and provides the basis for defining temperature and thermometry. Thermodynamics laws mcqs questions from this area often involve identifying equilibrium conditions between multiple systems and understanding how temperature comparisons are made without direct measurement.
Thermodynamics Laws MCQs :
1. The Zeroth law of thermodynamics leads to the concept of
A. Internal energy
B. Heat content
C. Pressure
D. Temperature
Answer: D
2. First law of thermodynamics is a consequence of the conservation of:
A. Energy
B. Charge
C. Heat
D. All of these
Answer: A
3. A constant volume gas thermometer works on
A. Archimedes’ principle
B. Pascal’s law
C. Boyle’s law
D. Charles’ law
Answer: D
4. First law of thermodynamics is represented by
A. dQ = dU + dW
B. dU = dW + pdV
C. dU = dQ + pdV
D. dU = dQ − pdV
Answer: A
5. Work done
A. Can only be positive
B. Can only be negative
C. Can either be positive or negative
D. None of these
Answer: C
6. Match the following lists
A. (a) II (b) IV (c) III (d) I
B. (a) III (b) IV (c) II (d) I
C. (a) III (b) I (c) II (d) IV
D. (a) I (b) III (c) IV (d) II
Answer: B
7. Which process is possible according to the first law of thermodynamics?
A. dQ > 0, Q < 0 and dU = 0
B. W > 0, Q < 0 and dU > 0
C. W < 0, Q > 0 and dU < 0
D. W < 0, Q > 0 and dU > 0
E. W > 0, Q < 0 and dU < 0
Answer: C
8. dU + dW = 0 is valid for
A. Adiabatic process
B. Isobaric process
C. Isothermal process
D. Isochoric process
Answer: A
9. If ΔU is increase in internal energy and W is work done by system, which is true?
A. ΔU = −W in an adiabatic process
B. ΔU = −W in an isothermal process
C. ΔU = −W in an isobaric process
D. ΔU = W in an adiabatic process
Answer: A
10. Which of the following relationships is correct?
A. E = mc
B. E = mc²
C. E = 2mc²
D. E = −mc² / 4
Answer: B
11. A system absorbs 2 kcal heat and does 500 J work. Change in internal energy is
A. 6400 J
B. 5400 J
C. 7900 J
D. 8900 J
Answer: C
12. First law of thermodynamics can be written as
A. ΔQ = ΔU + ΔW
B. ΔQ = ΔW + ΔU
C. ΔQ = ΔW − ΔU
D. ΔQ = ΔU − ΔW
Answer: B
13. A system is given 600 cal heat and does 600 J work. Change in internal energy is
A. −4.18 J
B. 654 J
C. −528.2 J
D. 300 J
Answer: A
14. If 150 J heat is added and internal energy is 40 J, work done is
A. 40 J
B. 70 J
C. 110 J
D. 150 J
Answer: B
15. If heat added is 150 J and work done is 110 J, ΔU is
A. 40 J
B. 110 J
C. 150 J
D. 260 J
Answer: A
16. State of a thermodynamic system is represented by
A. Pressure only
B. Volume only
C. Pressure, volume and temperature
D. Mixture of moles and temperature
Answer: C
17. If heat supplied is completely converted to work, the process is
A. Adiabatic
B. Isochoric
C. Isothermal
D. None of these
Answer: C
18. Heat is removed but no work is done. The wall is
A. Adiabatic
B. Closed system
C. Thermally conducting wall
D. Insulated wall
Answer: C
19. Zeroth law for three systems A, B, C implies
A. A and B in equilibrium
B. B and C in equilibrium
C. A and C in equilibrium
D. A, B and C in equilibrium
Answer: D
20. Law forming basis of temperature definition is
A. First law
B. Zeroth law
C. Second law
D. Third law
Answer: B
21. A thermodynamic function is
A. Work
B. Internal energy
C. Heat
D. Temperature
Answer: B
22. Match columns for first law
A. (a) III (b) II (c) IV (d) I
B. (a) III (b) IV (c) II (d) I
C. (a) IV (b) I (c) II (d) III
D. (a) I (b) III (c) IV (d) II
Answer: B
23. Quantity common for two systems in thermal equilibrium is
A. Heat
B. Momentum
C. Specific heat
D. Temperature
Answer: D
24. Prevost’s theory is not applicable at
A. 0 K
B. 0 °C
C. 0 °F
D. None of these
Answer: C
25. Work done in isothermal expansion depends on
A. Temperature only
B. Volume ratio only
C. Temperature and volume ratio
D. Initial and final pressure
Answer: C
26. Work obtainable from 200 cal heat is
A. 280 J
B. 800 J
C. 420 J
D. 840 J
Answer: D
27. If A is in equilibrium with B and B with C, then A and C are in
A. Thermal equilibrium
B. First
C. Second
D. Third
Answer: A
28. If ΔW = 0 and ΔQ < 0 for an ideal gas, then
A. Temperature decreases
B. Volume increases
C. Pressure constant
D. Temperature increases
Answer: A
29. Temperature and pressure where all three phases coexist is called
A. Sublimation point
B. Boiling point
C. Triple point
D. Fusion point
Answer: C
Conclusion on Thermodynamics Laws MCQs
Thermodynamics laws MCQs play a crucial role in building a strong conceptual foundation in physics by testing how well students understand the fundamental principles governing heat, work, energy, and temperature. The zeroth law establishes the idea of thermal equilibrium and provides the basis for temperature measurement, making it essential for understanding thermometers and thermal comparisons. Through thermodynamics laws MCQs on this law, learners develop clarity about equilibrium conditions and the consistency of temperature as a physical quantity.
The first law of thermodynamics, which embodies the conservation of energy, is central to many numerical and conceptual questions. Thermodynamics laws MCQs related to this law help students clearly distinguish between heat supplied, work done, and changes in internal energy under different thermodynamic processes such as isothermal, adiabatic, isobaric, and isochoric processes. Repeated practice with such thermodynamics laws mcqs questions strengthens problem-solving skills and prevents common sign-convention errors that often appear in exams.
Thermodynamics laws MCQs based on thermodynamic functions—such as internal energy, heat, and work—also sharpen the understanding of state and path variables. By analyzing these thermodynamics laws mcqs questions, students learn to identify which quantities depend only on the state of the system and which depend on the process followed.
Amal Augustine is the founder of ExQuizMe, a dynamic learning and quiz platform built to make education engaging, competitive, and fun. A passionate learner and an academic achiever, Amal completed his schooling at Government HSS Manjapra, graduating with 92.5% in Computer Science. He later earned his degree from St. Stephen’s College, University of Delhi, one of India’s most prestigious arts and science institutions.
Currently, Amal is pursuing his Master’s degree at National Sun Yat-sen University, Taiwan, where he continues to deepen his interest in research and technology. Throughout his school and college years, he won 50+ national-level interschool and collegiate quiz competitions, was
Beyond academics, Amal Augustine is an avid reader of science journals, a dedicated research student, and a technology enthusiast who loves programming and exploring the world of Computer Science. Through ExQuizMe, he aims to make learning accessible, enjoyable, and empowering for students across the globe.