Frequency German physicist Heinrich Hertz. One hertz means that an event repeats once per second. If a TV has a refresh rate of 1 hertz the TV's screen will change (or refresh) its picture once a second. A previous name for this unit was cycles per second (cps). The SI unit for period is the second. A traditional unit of measure used with rotating mechanical devices is revolutions per minute, abbreviated r/min or rpm. 60 rpm equals one hertz. As a matter of convenience, longer and slower waves, such as ocean surface waves, tend to be described by wave period rather
Angular frequency for the vector quantity angular velocity. One revolution is equal to 2π radians, hence where ω is referred to as the natural frequency (which can sometimes be denoted as ω). As the object oscillates, its acceleration can be calculated by where "x" is displacement from an equilibrium position. Using "ordinary" revolutions-per-second frequency, this equation would be The resonant angular frequency in a series LC circuit equals the square root of the reciprocal of the product of the capacitance ("C" measured in farads) and the inductance of the circuit ("L", with SI unit henry): Adding series resistance (for example, due to