Frequency Converters
Frequency measures how many times a repeating event occurs per unit of time. The SI unit is the hertz (Hz), equal to one cycle per second, named after physicist Heinrich Hertz. Frequency spans an enormous practical range: the human ear detects sound from about 20 Hz to 20,000 Hz; AM radio broadcasts in the kilohertz range; FM radio and mobile networks operate in megahertz; modern CPUs and Wi-Fi run in gigahertz; and infrared light occupies the terahertz range. Angular velocity — how fast something rotates — is a related concept expressed in radians per second or degrees per second, and is convertible to hertz by dividing by 2π. Rotational speed is also commonly quoted in revolutions per minute (RPM) and, for biological or musical contexts, beats per minute (BPM).