first law of thermodynamics

The first law of thermodynamics states that energy cannot be created or destroyed; it can only be transferred or changed from one form to another. In practical terms, when you add heat to a system, it may do work (like powering a motor) or increase the system’s internal energy (like warming up). Similarly, if the system performs work, its internal energy decreases accordingly. This principle ensures that total energy in a closed system remains constant, emphasizing the conservation of energy across processes and transformations.