Negative frequency Negative frequency The concept of negative and positive frequency can be as simple as a wheel rotating one way or the other way: a "signed value" of frequency can indicate both the rate and direction of rotation. The rate is expressed in units such as revolutions (a.k.a. "cycles") per second (hertz) or radian/second (where 1 cycle corresponds to 2"π" radians). Let "ω" be a nonnegative parameter with units of radians/sec. Then the angular function (angle vs. time) , has slope −"ω", which is called a negative frequency. But when the function is used as the argument of a cosine operator,
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