Given are statements for certain thermodynamic variables,
(A) Internal energy, volume (V) and mass (M) are extensive variables.
(B) Pressure (P), temperature (T) and density ( ) are intensive variables.
(C) Volume (V), temperature (T) and density ( ) are intensive variables.
(D) Mass (M), temperature (T) and internal energy are extensive variables.
Choose the correct answer from the points given below :
(A) Internal energy, volume (V) and mass (M) are extensive variables.
(B) Pressure (P), temperature (T) and density ( ) are intensive variables.
(C) Volume (V), temperature (T) and density ( ) are intensive variables.
(D) Mass (M), temperature (T) and internal energy are extensive variables.
Choose the correct answer from the points given below :
- (A)(C) and (D) only
- (B)(D) and (A) only
- (C)(A) and (B) only✓ Correct
- (D)(B) and (C) only
Answer: (C)
Solution
Extensive variables scale with the size (amount of matter) of the system: internal energy, volume, mass, entropy are all extensive.
Intensive variables do not depend on system size: pressure, temperature, density are all intensive.
(A) Internal energy, volume, mass — all extensive. True.
(B) Pressure, temperature, density — all intensive. True.
(C) Volume is extensive, not intensive, so this statement is false.
(D) Temperature is intensive, not extensive, so this statement is false.
Only (A) and (B) are correct.
Intensive variables do not depend on system size: pressure, temperature, density are all intensive.
(A) Internal energy, volume, mass — all extensive. True.
(B) Pressure, temperature, density — all intensive. True.
(C) Volume is extensive, not intensive, so this statement is false.
(D) Temperature is intensive, not extensive, so this statement is false.
Only (A) and (B) are correct.
JEE Main · 2025 · 22 Jan 2025 · Shift 2 · Single correct option