THERMODYNAMICS (First law of)
| Collection | International Encyclopedia of Systems and Cybernetics |
|---|---|
| Year | 2004 |
| Vol. (num.) | 2(2) |
| ID | ◀ 3534 ▶ |
| Object type | Discipline oriented, Methodology or model |
This law is also known as Law of the Conservation of Energy. In its original form the 1st law stated merely that in an isolated system, the total quantity of energy remained constant, even when transformed from one form into another (for instance, from mechanical to thermal by friction).
Later on, the law was extended to cover the conservation of the mass-energy complex, as for example in nuclear reactions.
The isolation condition is basic, since relationships with other systems or generally the environment would imply exchanges of energy.
Any isolated system has a characteristic energy level: its internal energy, which cannot be properly measured, since this should imply that the system be not anymore isolated: conceptual problems already lurk!