Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Concepts Of Physics MCQ Edition [Volume 2]
Exam
Concepts Of Physics MCQ Edition [Volume 2]
Subject
Physics
Chapter
Specific Heat Capacities of Gases

Concepts Of Physics MCQ Edition [Volume 2] · Physics · Specific Heat Capacities of Gases

As shown in the figure, a gas undergoes a process during which both...

As shown in the figure, a gas undergoes a process during which both its pressure and volume change. Let CC be the molar heat capacity for this process.
As shown in the figure, a gas undergoes a process during which both its pressure and volume change. Let C be the molar

Options

  1. AC>CVC > C_V
  2. BC<CVC < C_V
  3. CC=CVC = C_V
  4. DC=0C = 0

Correct answer

A. C>CVC > C_V

Step-by-step solution

From the given p−Vp-V graph, as the process proceeds, both pressure (pp) and volume (VV) of the gas increase. Therefore, dp>0dp > 0 and dV>0dV > 0.

According to the ideal gas equation, pV=nRTpV = nRT. Differentiating both sides, we get:
pdV+Vdp=nRdTp dV + V dp = nR dT

Since p,V,dpp, V, dp, and dVdV are all positive quantities, the change in temperature dTdT must also be positive (dT>0dT > 0).

From the first law of thermodynamics:
dQ=dU+dWdQ = dU + dW

For nn moles of gas, this can be written in terms of molar heat capacities as:
nCdT=nCVdT+pdVn C dT = n C_V dT + p dV

Dividing the entire equation by ndTn dT, we get the molar heat capacity CC for the process:
C=CV+pndVdTC = C_V + \dfrac{p}{n} \dfrac{dV}{dT}

Since p>0p > 0, n>0n > 0, dV>0dV > 0, and dT>0dT > 0, the term pndVdT\dfrac{p}{n} \dfrac{dV}{dT} is strictly positive.

Therefore, C>CVC > C_V.
Practice Specific Heat Capacities of Gases on Quantrex Academy →

More from Specific Heat Capacities of Gases

The ratio of molar heat capacities for an ideal gas is given as C_p / C_V = 7/6 . Find… Concepts Of Physics MCQ Edition [Volume 2]An ideal gas has a molar heat capacity ratio of C_p / C_V = 7/6 . Determine the change in… Concepts Of Physics MCQ Edition [Volume 2]As illustrated in the figure, a cylindrical container holds oxygen ( γ = 1.4 ) and is… Concepts Of Physics MCQ Edition [Volume 2]A vessel containing one mole of a monatomic ideal gas (molecular weight = 20 g mol^ -1 )… Concepts Of Physics MCQ Edition [Volume 2]When 50 J of heat is supplied to an ideal gas, it expands from 100 cm^3 to 200 cm^3 at a… Concepts Of Physics MCQ Edition [Volume 2]An ideal gas expands from 100 cm^3 to 200 cm^3 at a constant pressure of 2.0 × 10^5 Pa… Concepts Of Physics MCQ Edition [Volume 2]An ideal gas expands from 100 cm^3 to 200 cm^3 at a constant pressure of 2.0 × 10^5 Pa… Concepts Of Physics MCQ Edition [Volume 2]During a particular process, a monatomic ideal gas absorbs an amount of heat Q and… Concepts Of Physics MCQ Edition [Volume 2] Full Specific Heat Capacities of Gases list All Concepts Of Physics MCQ Edition [Volume 2] PYQs