NEETPhysicsThermodynamics
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): On a P-V diagram, the adiabatic curve is steeper than the isothermal curve for a given ideal gas. Reason (R): The magnitude of the slope of the isothermal curve is (ratio of specific heats) times the magnitude of the slope of the adiabatic curve at any given point. In the light of the above stateme
Options
- ABoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A)
- BBoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A)
- CAssertion (A) is true but Reason (R) is false
- DAssertion (A) is false but Reason (R) is true
Correct answer
C. Assertion (A) is true but Reason (R) is false
Step-by-step solution
The slope of an isothermal process on a P-V diagram is given by dP dV = - P V . The slope of an adiabatic process is given by dP dV = - P V . Since = C_p C_v > 1 for all ideal gases, the magnitude of the adiabatic slope is times the magnitude of the isothermal slope. This makes the adiabatic curve steeper than the isothermal curve. Therefore, the Assertion is correct, but the Reason is incorrect because it incorrectly states that the isothermal slope is times the adiabatic slope. Answer: Assertion (A) is true but R