Physics ISOTHERMAL PROCESS

Isothermal Process

For an isothermal process (T fixed), the ideal gas equation gives

PV = constant

i.e., pressure of a given mass of gas varies inversely as its volume. This is nothing but Boyle's Law.

Suppose an ideal gas goes isothermally (at temperature T ) from its initial state (`P_1, V_1`) to the final state (`P_2, V_2`). At any intermediate stage with pressure P and volume change from V to V + ΔV (ΔV small)

`ΔW = P Δ V`

Taking (ΔV → 0) and summing the quantity ΔW over the entire process,

`W=int_(V_1)^(V_2)PdV`

`W=nRTint_(V_1)^(V_2)(dV)/V`

`W=nRTln((V_2)/(V_1))`

 
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