fáza

Fáza is a term used in several scientific and technical contexts, most notably in physics and engineering, to describe a distinct, homogeneous, and mechanically separable part of a system. In thermodynamics, a phase refers to a region of space throughout which all physical properties of a material are essentially uniform. This includes properties like density, chemical composition, crystal structure, and refractive index. Common examples of phases in matter are solid, liquid, and gas. Transitions between these phases, such as melting, freezing, boiling, and condensation, occur at specific temperatures and pressures.

In electrical engineering, particularly in alternating current (AC) power systems, "phase" refers to the timing of an AC waveform relative to a reference point. A single-phase system uses a single alternating current, while a three-phase system uses three separate AC currents that are offset in time from each other by 120 degrees. This three-phase system is more efficient for transmitting large amounts of power and for operating electric motors.

The concept of phase can also be applied to waves, where it describes the position of a point in time on a waveform cycle. Two waves are said to be in phase if their crests and troughs align, and out of phase if they do not. In statistical mechanics, phase space is a theoretical construct that represents all possible states of a physical system, with each point in phase space corresponding to a unique combination of position and momentum for all particles in the system. Understanding the phase of a system is crucial for analyzing its behavior and predicting its properties.