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Questions
Write the mathematical equation for the first law of thermodynamics for:
Isothermal process
Deduce the first law of thermodynamics for the isothermal process.
Solution
For isothermal process:
For a given temperature (T) and internal energy (U) of the remains constant.
∴ ΔT = 0
∴ ΔU = 0
First law of thermodynamic
ΔU = Q + W
0 = Q + W ...(∵ ΔU = 0)
∴ Q = – W
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