What is the first law of thermodynamics?

The first law of thermodynamics states that energy cannot be created or destroyed, only transformed from one form to another, and that the total energy of an isolated system remains constant. This principle is often summarized by the concept of the conservation of energy. Therefore, the idea that energy is always conserved in an isolated system is fundamental to understanding how energy functions within that system.

In this context, the notion that energy can be created or destroyed does not align with the first law, as it directly contradicts the principle of conservation. The statement regarding entropy decreasing over time is more closely related to the second law of thermodynamics, which discusses the direction of energy transformations and the tendency of systems to move toward increased disorder. Lastly, the idea that energy is transferable but not transformable misrepresents the first law, as it emphasizes only one aspect of energy movement while neglecting its ability to change forms.