angular frequency

Angular frequency, also known as angular speed and usually denoted as \[\omega\], is a scalar measure of the angle per unit time or the rate of change if the phase of a sinusoidal waveform or sine function.

Angular speed is usually used when referring to the rate at which an object rotates in everyday or engineering scenarios, i.e. how fast an angle is changing over time. Angular frequency is more common in the context of oscillatory or wave phenomena, e.g. alternating currents or harmonic motion.

It is defined in:

• Circular motion (angular speed), i.e. \[\omega=\frac{d\theta}{dt}\].
  
• Uniform circular motion (angular speed), i.e. \[\omega=\frac{2\pi}{T}\].