Frequency is the number of occurrences of a repeating event per unit of time. It is measured in hertz (Hz), which is equal to the number of events per second. For example, if a heart beats at a frequency of 120 times a minute (2 Hz), the period—the interval at which the beats repeat—is half a second (60 seconds divided by 120 beats) . Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, sound waves, and electromagnetic radiation.
Some key points about frequency include:
- Unit: Frequency is measured in hertz (Hz), which is equal to the number of events per second.
- Period: The period (symbol T) is the interval of time between events, so the period is the reciprocal of the frequency, f=1/T.
- Electrical current: In the case of electrical current, frequency is the number of times a sine wave repeats, or completes, a positive-to-negative cycle. The more cycles that occur per second, the higher the frequency.
- Waves: Frequency describes the number of waves that pass a fixed place in a given amount of time.
