Quantum

An observable quantity is said to be quantized if its magnitude is restricted to a discrete set of values throughout at least part of its magnitude range. If the magnitude of a quantity is always a multiple of a fixed unit, the unit is called the quantum of the quantity. For example, when an analog audio signal is digitized to allow transmission via an Internet media stream the digitized audio signal can have magnitude values only at fixed multiples of a step value, so the step unit is a quantum of the digitized audio quantity. The magnitudes of many things that are commonly thought to exist in a continuous (analog) range of magnitudes are, in fact, restricted to multiples of a quantum. Electromagnetic radiation is an example. Electromagnetic radiation cannot exist at any arbitrary energy magnitude. It can exist only at discrete energy magnitudes that depend on the frequency. The quantum of energy of electromagnetic radiation of frequency v is hv, where h is Planck's constant. ©2005 Tigertek, Inc. All rights reserved.

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