Is there someone help me about thermodynamics

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The discussion focuses on understanding the application of thermodynamic formulas in adiabatic processes, specifically in the context of compressing air in a bicycle tire. The key equation mentioned is PV^γ = constant, where γ represents the ratio of heat capacities (Cp/Cv), which is approximately 1.4 for dry air at room temperature. Participants clarify that knowing the initial pressure and volume allows for the calculation of the final volume after compression to 7 atm using this equation. The conversation emphasizes the importance of recognizing the constants involved in adiabatic processes to solve such problems effectively. Understanding these principles is crucial for applying thermodynamics in practical scenarios.
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ı don't understand how i am going to use the formula of thermodynamics in adiabatic. actually there are a lots of constant in adiabatic..

the question is :
In the course of pumping up a bicycle tire, a liter of air at atmospheric pressure is compressed adiabatically to a pressure of 7 atm. (Air is mostly diatomic nitrogen and oxygen.)
(a)
What is the final volume of this air after compression?
PV^gamma = const i am trying but i cat..
thaks for helping me about that now
 
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opeth_35 said:
ı don't understand how i am going to use the formula of thermodynamics in adiabatic. actually there are a lots of constant in adiabatic..

the question is :
In the course of pumping up a bicycle tire, a liter of air at atmospheric pressure is compressed adiabatically to a pressure of 7 atm. (Air is mostly diatomic nitrogen and oxygen.)
(a)
What is the final volume of this air after compression?
PV^gamma = const i am trying but i cat..
thaks for helping me about that now
what is \gamma?
You know the initial P and the initial V, so what is PV^{\gamma}?
You know that this value is equal to P_{final}V_{final}^{\gamma}. So you now have one equation and one unknown, so you can solve that.

AM
 
gamma is the ratio of heat capacities, Cp/Cv
For dry air at room temperature gamma is 1.4.
It's good to memorize this because it is seen in numerous cituations, such as otto cycles.
 
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