The cycle per second was a once-common unit of frequency Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency. The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency. Loosely speaking, 1 year is the period of the Earth's orbit around the Sun, and the Earth's rotation on its axis has.
With the organisation of the International System of Units The International System of Units is the modern form of the metric system and is generally a system of units of measurement devised around seven base units and the convenience of the number ten. It is the world's most widely used system of measurement, both in everyday commerce and in science (abbreviated SI from the French) in 1960, the cycle per second was officially replaced by the hertz The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of sine wave, particularly those used in radio and audio applications, or reciprocal second—i.e. the cycle in 'cycle per second' was dropped. Perhaps because of the convenient brevity it brings to both speech and writing, this particular mandate has been so widely adopted as to render the old 'cycle per second' all but extinct.
Nonetheless, the change is not without its critics, who argue that the hertz should be redefined as simply a renaming of the cycle per second it displaced, rather than as the reciprocal second. Since SI has adopted the radian The radian is the standard unit of angular measure, used in many areas of mathematics. It describes the plane angle subtended by a circular arc as the length of the arc divided by the radius of the arc. The unit was formerly a SI supplementary unit, but this category was abolished in 1995 and the radian is now considered a SI derived unit. The SI as its preferred but dimensionless unit of angle In geometry, an angle is the figure formed by two rays sharing a common endpoint, called the vertex of the angle. The magnitude of the angle is the "amount of rotation" that separates the two rays, and can be measured by considering the length of circular arc swept out when one ray is rotated about the vertex to coincide with the other, but left its explicit writing discretionary in unit combinations, the radian per second has perhaps a better claim than the cycle per second to being equivalent to the reciprocal second. But the hertz is overwhelmingly (some would say exclusively) used in the sense of cycle per second, and certainly never used in the sense of radian per second.
The obsolete terms kilocycle, megacycle and kilomegacycle still occur in some older documents; the modern equivalents are kilohertz, megahertz and gigahertz, respectively.
| This mathematics Mathematics is the study of quantity, structure, space, and change. Mathematicians seek out patterns, formulate new conjectures, and establish truth by rigorous deduction from appropriately chosen axioms and definitions-related article is a stub. You can help Wikipedia by expanding it. |
Categories: Units of frequency |
