👉 A fluid, in the context of physics and thermodynamics, is a substance that takes the shape of its container but has no fixed volume, instead flowing and adapting to fill any space it occupies. This characteristic distinguishes fluids from solids and gases, where the latter have fixed volumes and shapes. Liquids, a common type of fluid, exhibit properties like viscosity, allowing them to flow but resist deformation, and they can be compressed to some extent under pressure. The behavior of fluids is governed by principles such as Pascal's law, which states that pressure applied to a confined fluid is transmitted equally throughout the fluid, illustrating their unique and versatile nature in physical systems.
