Sound Frequency and Vibrations

Production of Sound Through Vibrations

Frequency

A sound is a form of energy that arises when air molecules vibrate in a specific manner known as waves. The vibration that produces a sound can be attributed to an object's oscillatory motion, characterized as the movement of the object from one point to another in a periodic time. This motion is referred to as an oscillation, where each oscillation represents the complete movement between the two endpoints of the motion.

The frequency of an oscillation signifies the number of oscillations an object undergoes per second. The unit of measurement for frequency is the Hertz (Hz), representing one oscillation per second. Higher frequencies correspond to faster oscillations, yielding sounds that are perceived as higher pitched. Conversely, slower oscillations produce sounds with lower pitch.

The human ear is sensitive to sound in a frequency range of approximately 20Hz to 20kHz. Within this audible range, the ear is most responsive to frequencies around 2000–3000Hz. Sounds below 20Hz are categorized as infrasonic or infrasound, while those above 20kHz are classified as ultrasonic or ultrasound. Different animals possess varying ranges of hearing; for instance, dogs can detect sounds up to about 50kHz, bats can hear sounds up to roughly 100kHz, dolphins can discern sounds of even higher frequencies, elephants and whales are capable of hearing sounds below 20Hz, and some fishes can detect frequencies as low as 1–25Hz.