NeetVictoryQuestion 1: First Law of Thermodynamics
The internal energy of 1 mol of a diatomic ideal gas at 300 K is about (R = 8.31 J/mol K):
- A 6.2 kJ
- B 2.5 kJ
- C 3.7 kJ
- D 12.5 kJ
Answer: A. 6.2 kJ
Why: U = (5/2)RT = 2.5 × 8.31 × 300 ≈ 6.2 kJ.
NEET Physics: Thermodynamics. Chapter-wise Practice Questions and Test
Thermodynamics is a Class 11 Physics chapter that carries about 2.8% of the Physics questions in NEET. Practise it with 40 questions covering 2 topics, each with an explanation.
Practise Thermodynamics
Open in the appSets of 15 questions that adapt to your level, with an explanation for every answer.
Topics covered in Thermodynamics
- First Law of Thermodynamics (19 questions)
- Thermodynamic Processes (Isothermal, Adiabatic) (21 questions)
How often Thermodynamics has come up in NEET
Across the 13 previous year papers, Thermodynamics had 19 questions, about 1.5 a year. The most in one paper was 3, in NEET 2018.
| Paper | Questions from this chapter |
|---|---|
| NEET 2026 | 1 |
| NEET 2025 | 1 |
| NEET 2024 | 2 |
| NEET 2023 | 1 |
| NEET 2022 | 1 |
| NEET 2021 | 0 |
| NEET 2020 | 1 |
| NEET 2019 | 1 |
| NEET 2018 | 3 |
| NEET 2017 | 2 |
| NEET 2016 | 2 |
| Re-AIPMT 2015 | 2 |
| AIPMT 2014 | 2 |
Sample questions on Thermodynamics with answers
8 questions from the practice bank, spread across the chapter's topics. The full set is in the app.
Question 2: Thermodynamic Processes (Isothermal, Adiabatic)
A refrigerator works between 270 K inside and 300 K outside. Its maximum coefficient of performance is:
- A 10
- B 0.9
- C 9
- D 30
Answer: C. 9
Why: COP = T_cold/(T_hot − T_cold) = 270/30 = 9.
Question 3: First Law of Thermodynamics
The molar heat capacities at constant volume and constant pressure for a diatomic gas at room temperature are:
- A 5R/2 and 7R/2
- B 7R/2 and 9R/2
- C 3R/2 and 5R/2
- D R and 2R
Answer: A. 5R/2 and 7R/2
Why: A diatomic molecule has 5 active degrees of freedom, so γ = 7/5.
Question 4: Thermodynamic Processes (Isothermal, Adiabatic)
When an ideal gas expands adiabatically, its temperature:
- A rises
- B stays constant
- C becomes zero
- D falls
Answer: D. falls
Why: With Q = 0, the gas does work at the expense of its internal energy, so ΔU is negative and the temperature drops.
Question 5: First Law of Thermodynamics
A gas is given 500 J of heat and does 200 J of work. The change in its internal energy is:
- A 700 J
- B 100 J
- C −300 J
- D 300 J
Answer: D. 300 J
Why: ΔU = Q − W = 500 − 200 = 300 J.
Question 6: Thermodynamic Processes (Isothermal, Adiabatic)
A monatomic ideal gas (γ = 5/3) is compressed adiabatically to half its volume. Its temperature changes by a factor of:
- A 1/2
- B 2^(5/3)
- C 2
- D 2^(2/3)
Answer: D. 2^(2/3)
Why: TV^(γ−1) is constant, so T₂/T₁ = 2^(2/3) ≈ 1.59.
Question 7: First Law of Thermodynamics
Among the following, the quantities that are state functions are:
- A internal energy and temperature
- B heat and internal energy
- C work and temperature
- D heat and work
Answer: A. internal energy and temperature
Why: Heat and work depend on the path followed.
Question 8: Thermodynamic Processes (Isothermal, Adiabatic)
The efficiency of a Carnot engine working between 500 K and 300 K is:
- A 60%
- B 40%
- C 80%
- D 20%
Answer: B. 40%
Why: η = 1 − T₂/T₁ = 1 − 300/500 = 0.4.
Practise all of Thermodynamics
Open in the appFrequently asked questions
How many questions come from Thermodynamics in NEET?
Thermodynamics carries about 2.8% of the Physics questions in NEET. Across the 13 previous year papers on NeetVictory it appeared 19 times, about 1.5 questions a year.
Which class is Thermodynamics from?
Thermodynamics is a Class 11 Physics chapter in the NCERT syllabus.
Where can I practise Thermodynamics questions for NEET?
NeetVictory has 40 practice questions on Thermodynamics, each with an explanation, in sets of 15 that adapt to your level. This page shows a free sample.