Insulation=> simple problem just confused a bit.

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SUMMARY

The discussion focuses on calculating the energy required to increase the temperature of a diatomic gas contained in a well-insulated volume of 100m³ at 300K. The relevant equations include Q = mC_vΔT for constant volume, where C_v = 5R/2, and Q = mC_pΔT for constant pressure, where C_p = 7R/2. Additionally, the discussion addresses how to determine the mass of an object that can be lifted using the calculated energy, employing the equation ΔPE = mgh. The consensus is that the volume remains constant during the temperature increase.

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  • Understanding of thermodynamics, specifically the concepts of heat transfer and internal energy.
  • Familiarity with the properties of diatomic gases and their specific heat capacities (C_v and C_p).
  • Knowledge of the ideal gas law and its applications in thermodynamic calculations.
  • Basic understanding of potential energy and gravitational force equations.
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  • Study the derivation and application of the ideal gas law in thermodynamic processes.
  • Learn about the differences between isochoric and isobaric processes in thermodynamics.
  • Explore the concept of specific heat capacities for various gas types and their implications in energy calculations.
  • Investigate the relationship between work done and energy transfer in mechanical systems.
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Students studying thermodynamics, particularly those preparing for quizzes or exams in physics or engineering courses. This discussion is also beneficial for anyone needing clarity on energy calculations involving gases.

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Homework Statement


A house has well insulated walls. It contains a vol of 100m^3 of air at 300K

a) calculate the E required to increase the T of the diatomic gas by 1.00C

b) If this E could be used to lift an object of mass m through a height of 2.00m what is the mass of m?


Homework Equations


Q=m C_v \Delta T= > constant V
\Delta U= Q
C_v= 5R/2

Q=mC_p \Delta T=> constant P
\Delta U= Q + W= nC_p \Delta T + (-P\Delta V)
C_p= 7R/2

The Attempt at a Solution



a)calculate the E required to increase the T of the diatomic gas by 1.00C

I would think that the insulation would make the volume be constant but that's what I'm not sure about. (I was thinking that the temperature would be constant but if they ask how much E is needed to raise the temperature then it can't be that the temperature would be the same...)

b) b) If this E could be used to lift an object of mass m through a height of 2.00m what is the mass of m?
would I just use \Delta PE= mghand find m ?

Help please..

Thank you very much.
 
Last edited:
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can someone help me please?

I have a quiz and if no one does then I'll be forced to assume that the volume doesn't change even if it may be incorrect. :frown:
 

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