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Show that for monoatomic gas the ratio of the two specific heats is 5:3. - Physics

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प्रश्न

Show that for monoatomic gas the ratio of the two specific heats is 5:3. 

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उत्तर

  1. For a monatomic gas enclosed in a container, held at a constant temperature T, and containing NA atoms, each atom has only 3 translational degrees of freedom. 
  2. Therefore, the average energy per atom is `3/2` kBT and the total internal energy per mole is, E = `3/2` NAkBT  
  3. Molar specific heat at constant volume
    Cv = `"dE"/"dT" = 3/2"N"_"A""k"_"B" = 3/2"R"`
  4. Using Mayer’s relation, CP = R + C
    ∴ Cp = `5/2`R
    ∴ `"C"_"p"/"C"_"v" = 5/3`
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Gases and Its Characteristics
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अध्याय 3: Kinetic Theory of gases and Radiation - Short Answer I

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एससीईआरटी महाराष्ट्र Physics [English] 12 Standard HSC
अध्याय 3 Kinetic Theory of gases and Radiation
Short Answer I | Q 2

संबंधित प्रश्न

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Column B 

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(b)

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