What principle states that the total energy in an isolated system remains constant?

The principle that states the total energy in an isolated system remains constant is known as the Conservation of Energy. This fundamental concept in physics indicates that energy cannot be created or destroyed; it can only change from one form to another. For example, in a closed system, the energy can shift between kinetic energy (energy of motion) and potential energy (stored energy), but the total amount of energy remains unchanged.

This principle is crucial in various fields of science and engineering as it allows for the calculation and prediction of energy transformations within physical systems. Understanding the Conservation of Energy helps students and professionals analyze how energy flows and interacts in real-world situations, such as in mechanical systems, electrical circuits, and thermal processes.

The other options refer to different concepts: Bernoulli's Principle deals specifically with fluid dynamics and how fluid velocity and pressure relate to each other; Newton's Law encompasses a range of laws regarding motion and force; and Thermodynamics involves the study of heat transfer and the relationships between heat, work, and energy. Thus, they do not directly state the key idea of energy conservation in isolated systems.