Question

In thermodynamic processes, which of the following statements is not true?

• A. In an isothermal process, the temperature remains constant
• B. In an isobaric process, the volume remains constant
• C. In an adiabatic process, the system is insulated from the surroundings
• D. In an adiabatic process, $PV^\gamma$ = a constant

Hint:

Remember the prefixes:
- \textbf{Iso}thermal: Constant \textbf{T}emperature.
- \textbf{Iso}baric: Constant \textbf{P}ressure.
- \textbf{Iso}choric: Constant \textbf{V}olume.
- \textbf{Adia}batic: No heat \textbf{transfer}.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The question asks to identify the incorrect statement among those describing different types of thermodynamic processes.
Step 3: Detailed Explanation:
Let's analyze each statement:
(1) Isothermal process: A process where the temperature of the system remains constant throughout. This statement is true.
(2) Isobaric process: A process where the pressure of the system remains constant. If the volume remains constant, it is an isochoric (or isovolumetric) process. Therefore, this statement is not true.
(3) Adiabatic process: A process where no heat is exchanged between the system and its surroundings. This implies the system is perfectly insulated. This statement is true.
(4) Adiabatic process: For an ideal gas undergoing an adiabatic process, the relationship between pressure and volume is $PV^\gamma = \text{constant}$, where $\gamma$ is the ratio of specific heats ($C_p/C_v$). This statement is true.
Step 4: Final Answer:
The statement that is not true is (2).