What physical principle describes how energy is never lost but transforms from one form to another?

The principle that describes how energy is never lost but instead transforms from one form to another is the conservation of energy. This fundamental concept in physics states that the total amount of energy in an isolated system remains constant over time. It can change from one form to another—such as from kinetic energy to potential energy or from mechanical energy to thermal energy—but the overall energy is conserved.

This principle plays a crucial role in many areas of science and engineering, as it allows us to analyze systems and predict how they will behave under different conditions. For instance, in a roller coaster, the energy transforms from potential energy at the top of a hill to kinetic energy as it descends, showcasing the conservation of energy in action.

In contrast, other concepts such as Newton's First Law pertains to inertia and motion, Hooke's Law relates to the behavior of springs regarding force and displacement, and Bernoulli's Principle describes the behavior of fluid dynamics. These principles, while important in their respective areas, do not encapsulate the idea of energy transformation and conservation as effectively as the conservation of energy does.