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Clara Chung
- 304
- 14
I know that dS=dQ/T for reversible process,
is dU=TdS-PdV for reversible process only?
is dU=TdS-PdV for reversible process only?
This equation has nothing to do with any process. It is a physical property relationship that must be satisfied for any material, describing the relationship between the mutual changes in U, S, and V between and two closely neighboring thermodynamic equilibrium states of the material. This constraint is imposed as a consequence of the 2nd law of thermodynamics.Clara Chung said:I know that dS=dQ/T for reversible process,
is dU=TdS-PdV for reversible process only?
The first law of thermodynamics is the principle of conservation of energy, stating that energy cannot be created or destroyed, only transferred or converted from one form to another.
The first law of thermodynamics states that the total energy of a closed system remains constant. This means that any heat added to a system must either be converted into work or increase the internal energy of the system.
No, the first law of thermodynamics is a fundamental law of nature and cannot be violated. It has been extensively tested and proven to hold true in all physical and chemical processes.
An example of the first law of thermodynamics is a car engine, where the chemical energy from the fuel is converted into heat, which is then converted into mechanical energy to move the car.
The first law of thermodynamics sets a limit on the maximum efficiency of any energy conversion process. This means that it is impossible to convert 100% of the energy input into useful work, as some energy will always be lost in the form of heat.