Comparison b/w work done in adiabatic & isothermal processes

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babita
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Homework Statement



In the graph attached, why is isothermal graph line higher than adiabatic one??

Homework Equations





The Attempt at a Solution


At first, i had thought that work done in an isothermal process is greater than in an adiabatic process...but for comparison we would need same initial and final states (P & V) , wouldn't we?
 

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The area under the graph is the work done by the gas (W=∫PdV)

You can compare those areas and see that in an isothermal process the work done is indeed higher than in an adiabatic process.

For a proper comparison you would need indeed the same final P&V.
So introduce an extra isochoric (constant volume) process step (a vertical line in your diagram) and presto!
 
i know that.... my doubt was that P & V which are describing the state should be same(initial and final), then we can compare the work done through 2 ways: adiabatic & isothermal
but i have got it..the graph simply indicates that if we expand a gas and do it isothermally it would require more work to be done
thanks :)