An isothermal process is a thermodynamic process in which the temperature of the system remains constant throughout the process.
For isothermal process:
ΔU = 0
Q = W
Example: Slow expansion or compression of gas in contact with a heat reservoir.
An adiabatic process is a thermodynamic process in which no heat is exchanged between the system and surroundings.
For adiabatic process:
Q = 0
ΔU = −W
Example: Rapid expansion or compression of gas.
| Isothermal Process | Adiabatic Process |
|---|---|
| Temperature constant | Temperature changes |
| Heat exchange occurs | No heat exchange |
| ΔU = 0 | ΔU ≠ 0 |
| Slow process | Rapid process |
Q1. In an isothermal process, which quantity remains constant? A) Pressure B) Volume C) Temperature D) Internal energy Answer: C Q2. For an isothermal process, change in internal energy is: A) Positive B) Negative C) Zero D) Maximum Answer: C Q3. In an adiabatic process: A) Heat exchange occurs B) Temperature remains constant C) No heat is exchanged D) Internal energy remains zero Answer: C Q4. In an adiabatic process, the relation between ΔU and W is: A) ΔU = W B) ΔU = −W C) ΔU = Q D) ΔU = 0 Answer: B Q5. Slow expansion of gas is an example of: A) Adiabatic process B) Isothermal process C) Isochoric process D) Isobaric process Answer: B Q6. Rapid compression of gas is an example of: A) Isothermal process B) Isochoric process C) Adiabatic process D) Isobaric process Answer: C Q7. In which process Q = W? A) Adiabatic B) Isochoric C) Isothermal D) Isobaric Answer: C Q8. In an adiabatic process, heat supplied is: A) Maximum B) Minimum C) Zero D) Infinite Answer: C
MCQs and numericals are frequently asked on difference, formulas and identification of isothermal and adiabatic processes.
