Calculating work done on a gas- Adiabatic process PV diagram.

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SUMMARY

The discussion focuses on calculating work done on a gas during an adiabatic process using the PV diagram. The equation for work, W = - ∫P dV, is utilized, with P expressed as a function of volume using the relation P = constant / V^gamma. The user successfully integrates to find W = constant * (Vf^(1-gamma) - Vi^(1-gamma)) / (1-gamma) but struggles to determine the constant from the provided graph. The correct expression for the constant is derived as (Pi * Vi)^gamma / (Pf * Vf)^gamma.

PREREQUISITES
  • Understanding of adiabatic processes in thermodynamics
  • Familiarity with integration techniques in calculus
  • Knowledge of the ideal gas law and its applications
  • Experience with PV diagrams and graphical analysis of thermodynamic processes
NEXT STEPS
  • Study the derivation of the adiabatic process equations in thermodynamics
  • Learn about Riemann sums and their application in calculating integrals
  • Explore the implications of the gamma (γ) factor in adiabatic processes
  • Investigate graphical methods for determining constants in thermodynamic equations
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Students studying thermodynamics, physics enthusiasts, and anyone looking to deepen their understanding of work calculations in adiabatic processes.

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Homework Statement



As per attachment. Part iii

How would you do this question by integrating the work?

Homework Equations



W = - ∫P dV

PV^gamma = constant


The Attempt at a Solution



So I integrated the work with P= constant/ V^gamma and came up with this:

W = constant* ( Vf^(1-gamma)-Vi^(1-gamma) ) / (1-gamma)


So now how to I find the constant from the graph and information provided. This is what I was trying to do with not much luck:

constant = (Pi* Vi)^gamma / (Pf* Vf)^gamma

Am I missing something obvious?

Thanks in advance.
 

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Have you done this before? Draw yourself some riemann rectangles and maybe you'll see how you have to set this up. Think about x and y and then look at what you have, hopefully you'll see what you need to do.
 
Show us the details of how you did the integration, and we will be able to help you. Otherwise, it's hard to point out where your problem is from just your final equations.

Chet
 

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