Insulation=> simple problem just confused a bit.

AI Thread Summary
The discussion revolves around calculating the energy required to increase the temperature of a diatomic gas in a well-insulated house. The user seeks clarification on whether the volume remains constant during the temperature increase, as this affects the calculations. For part a, they are uncertain about the implications of insulation on temperature changes, while for part b, they inquire if they can use the potential energy formula to find the mass that can be lifted with the calculated energy. The user expresses urgency due to an upcoming quiz and requests assistance to confirm their understanding. Overall, the thread highlights confusion about thermodynamic principles in a practical context.
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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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