Physics: Thermodynamics
31. Question
An engine takes in 5 mole of air at 20°C and 1 atm, and compresses it adiabaticaly to 1/10 th of the original volume. Assuming air to be a diatomic ideal gas made up of rigid molecules, the change in its internal energy during this process comes out to be X kJ. The value of X to the nearest integer is ________.
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32. Question
A balloon filled with helium (32°C and 1.7 atm.) bursts. Immediately afterward the expansion of helium can be considered as :
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33. Question
In an adiabatic process, the density of a diatomic gas becomes 32 times its initial value. The final pressure of the gas is found to be n times the initial pressure. The value of n is :
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34. Question
Match the thermodynamic processes taking place in a system with the correct conditions. In the table: ΔQ is the heat supplied, ΔW is the work done and ΔU is change in internal energy of the system.
| Process | Condition |
| (I) Adiabatic | (A) ΔW = 0 |
| (II) Isothermal | (B) ΔQ = 0 |
| (III) Isochoric | (C) ΔU ≠ 0, ΔW ≠ 0, ΔQ ≠ 0 |
| (IV) Isobaric | (D) ΔU = 0 |
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35. Question
Three different processes that can occur in an ideal monoatomic gas are shown in the P vs V diagram. The paths are labeled as A → B, A →C and A → D. The change in internal energies during these processes are taken as EAB , EAC and EAD and the workdone as WAB , WAC, and WAD. The correct relation between these parameters are :
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