P-V diagram

A P-V diagram, or pressure-volume diagram, is a graph that shows the relationship between the pressure inside a gas or fluid and its volume. It's commonly used in thermodynamics to visualize how gases behave during processes like compression or expansion. The horizontal axis represents volume, while the vertical axis represents pressure. The shape of the curve indicates how pressure and volume change together, revealing important information about energy transfer, work done, and efficiency in processes such as engines or refrigerators. It helps engineers and scientists analyze and design systems involving gases more effectively.