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Isothermal versus adiabatic change: compare the final pressures

This type of question, asked 9 times: 3 May 2023 S1, 10 May 2023 S1, 11 May 2023 S1, 11 May 2024 S1, 19 Apr 2025 S1, 11 Apr 2026 S1, 16 Apr 2026 S1, 18 Apr 2026 S2, 20 Apr 2026 S2. All 9 questions below, oldest first.

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  1. Question 1

    3 May 2023 S1

    20
    There are two samples A and B of a certain gas, initially at the same temperature and pressure. Both are compressed from volume VV to V2\frac{V}{2}. Sample A is compressed isothermally while sample B is compressed adiabatically. The final pressure of A is

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  2. Question 2

    10 May 2023 S1

    37
    Initial pressure and volume of a gas are 'P' and 'V' respectively. First its volume is expanded to '4V' by isothermal process and then again its volume is reduced to 'V' by adiabatic process; then its final pressure if γ=32\gamma=\frac{3}{2}

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  3. Question 3

    11 May 2023 S1

    19
    Two gases A and B having same initial state (P,V,n,T). Now gas A is compressed to V8\frac{V}{8} by isothermal process and other gas B is compressed to V8\frac{V}{8} by adiabatic process. The ratio of final pressure of gas A and B is (Both gases are monoatomic, γ=5/3\gamma = 5/3)

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  4. Question 4

    11 May 2024 S1

    37
    A monoatomic gas at pressure P, having volume V expands isothermally to a volume 2V and then adiabatically to a volume 16V. The final pressure of the gas is (Take γ=5/3\gamma = 5/3)

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  5. Question 5

    19 Apr 2025 S1

    13
    Three samples X,YX,Y, and Z of same gas have equal volumes and temperatures. The volume of each sample is doubled, the process being isothermal for X , adiabatic for Y and isobaric for Z . If the final pressures are equal for the three samples, the ratio of the initial pressures is ( γ=3\gamma= 3 / 2)

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  6. Question 6

    11 Apr 2026 S1

    116
    Two samples A and B of gas initially at the same pressure and temperature. They are compressed from volume VV to V2\dfrac{V}{2} (A isothermally and B adiabatically). The relation between pressure of the gas A (PA)(P_A) and pressure of gas B (PB)(P_B) is

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  7. Question 7

    16 Apr 2026 S1

    117
    A monoatomic gas at pressure P having volume V expands isothermally to a volume 3V and then adiabatically to a volume 81 V. The final pressure of the gas is (γ=5/3)(\gamma = 5/3).

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  8. Question 8

    18 Apr 2026 S2

    115
    An ideal gas with pressure P, volume V and temperature T is expanded isothermally to volume 2V and a final pressure PiP_i. The same gas is expanded adiabatically to a volume 2V then the final pressure is PaP_a. In terms of γ\gamma, the ratio of the two specific heats for the gas, the ratio Pi/PaP_i/P_a is

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  9. Question 9

    20 Apr 2026 S2

    117
    An ideal gas having pressure PP, volume VV and temperature TT is expanded isothermally, to a volume 3V3V and final pressure PIP_I. The same gas is expanded adiabatically to a volume 3V3V, the final pressure being PAP_A. The ratio PAPI\dfrac{P_A}{P_I} is (CPCV=γ)\left(\dfrac{C_P}{C_V} = \gamma\right)

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