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Can a Process on an Ideal Gas Be Both Adiabatic and Isothermal?

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प्रश्न

Can a process on an ideal gas be both adiabatic and isothermal?

थोडक्यात उत्तर
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उत्तर

According to the first law of thermodynamics, change in internal energy, ΔU is equal to the difference between heat supplied to the gas, Δ Q and the work done on the gas,​ ΔW, 

such that ΔQ = ΔU +ΔW . In an adiabatic process, ΔQ =0  and in an isothermal  process, change in temperature, Δ T =0. Therefore,

ΔQ = ΔU + ΔW

⇒ ΔQ = nCvΔT +ΔW

⇒ 0 =nCv(0) + Δ W

⇒ Δ W = 0 ,

if the process is adiabatic as well as isothermal, no work will be done. So, a process on an ideal gas cannot be both adiabatic and isothermal.

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पाठ 27: Specific Heat Capacities of Gases - Short Answers [पृष्ठ ७६]

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एचसी वर्मा Concepts of Physics Volume 1 and 2 [English]
पाठ 27 Specific Heat Capacities of Gases
Short Answers | Q 6 | पृष्ठ ७६

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