Frequency measures how often a particular event or cycle occurs within a specific period of time. In oscillations, vibrations or waves, frequency is the phenomenon used to describe the repetitive nature. In this article we will discuss frequency units.
The standard unit of frequency is hertz (Hz) and hertz equals one cycle per second.
When scaled up, kilohertz (kHz), megahertz (MHz), gigahertz (GHz), and terahertz (THz) are used to measure frequency.
Frequency is a fundamental concept in physics and is applied in numerous fields, including telecommunications, electronics, acoustics, and many other scientific and engineering disciplines.
Some of the common frequency units are as follows.
Hertz (Hz):
Hertz is the standard unit of frequency in the International System of Units (SI). Represents one cycle per second. For example, a frequency of 50 Hz means that one second contains 50 cycles.
Kilohertz (kHz):
One kilohertz is equal to one thousand hertz. It is commonly used to measure frequencies in radio communications, audio signals, and certain electronic devices.
Megahertz (MHz):
One megahertz is equal to one million hertz. It is often used to specify frequencies in radio and television, as well as in computer processors.
Gigahertz (GHz):
One gigahertz is equal to one billion hertz. The value is often used in discussions about the speed of computer processors, radio frequency communication systems, and some medical imaging technologies.
Terahertz (THz):
One terahertz is equal to one trillion hertz. It is used in advanced scientific and technological applications, including spectroscopy, imaging, and certain types of wireless communications.
Revolutions per minute (RPM):
Although not an SI unit, the revolution per minute is often used to express the frequency of rotating machines such as engines, turbines, and fans.
Cycles per second (cps):
This is an older term for hertz, which expresses the number of cycles or oscillations in one second. Although it has largely been replaced by Hertz in modern usage, it is still occasionally encountered.
Radians per second (rad/s):
Radians per second express the angular frequency and represent the speed of rotation in a circular motion. It is often used in physics and engineering, especially in the study of oscillating systems.
Beats per minute (BPM):
Although not a formal unit, beats per minute are often used in music to express the tempo or speed of a piece of music. This is also a type of frequency representation.
one hundred pesos per acre-foot:
In the context of water management, this unconventional unit expresses the frequency of flow in a canal or river and represents the flow required to cover one acre-foot of land.
These units offer diverse ways of expressing frequencies in a wide range of applications, from microscopic vibrations of atoms to the rotation of giant machines.
There are five other types of frequency-related units:
Millihertz (mHz):
One millihertz is equal to one thousandth of a hertz. It is used to measure extremely low frequencies commonly found in scientific research and specialized equipment.
Microhertz (μHz):
A microhertz is one millionth of a hertz. It is used for precision measurements, for example in extremely slow processes or environmental phenomena.
Nanohertz (nHz):
One nanohertz is equal to one billionth of a hertz. It is often used to study very low frequency gravitational waves and to determine the timings of pulsars.
Petahertz (PHZ):
One petahertz is equal to one quadrillion hertz. It is used in discussions of extremely high frequency electromagnetic waves, particularly in the terahertz and infrared ranges.
Hertz Angle (Hzrad):
Although not a standard unit, angular hertz is used to express angular frequency in radians per second and provides a measure of how quickly an angle changes over time.
These additional units provide more specialized frequency measurement capabilities and meet a variety of scientific and engineering needs.