Physics Thermodynamics KU 2024
PMDC Verified Question 8 of 54
During an isothermal expansion of an ideal gas, which of the following statement is true?
A
The temperature of the gas remains constant
B
Pressure and temperature of the gas increase
C
The internal energy of the gas increases
D
The work done by the gas is zero
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: The temperature of the gas remains constant
1. Concept:

Thermodynamic nomenclature strictly dictates the physical parameters of the process. 'Isothermal' directly defines the thermal state.

2. Formula:

$$\Delta T = 0$$

3. Solution:

  • The prefix 'iso' denotes equality or constancy. 'Thermal' relates to temperature.


  • Therefore, by strict definition, an isothermal expansion occurs in such a slow, heat-exchanging manner that the temperature of the gas is maintained absolutely constant.


4. Why other options are incorrect:

In isothermal expansion, pressure drops (not increases), work is definitely done (not zero), and internal energy remains constant (does not increase).

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