Sound waves can vary in frequency and intensity, giving rise to a wide range of audible sounds. The human hearing range is typically considered to be from 20 Hz (hertz) to 20,000 Hz, although this range can vary slightly from person to person.
The frequency of a sound wave determines its pitch, with higher frequencies corresponding to higher pitches and lower frequencies corresponding to lower pitches. For example, a sound wave with a frequency of 1,000 Hz would be perceived as a higher pitch than a sound wave with a frequency of 100 Hz.
The intensity of a sound wave determines its loudness or volume. Intensity is measured in decibels (dB), and the range of intensities that humans can perceive is vast. The threshold of human hearing, the softest sound that can be detected, is generally considered to be around 0 dB. As the intensity increases, the sound becomes louder, with typical conversational speech ranging from 60 to 70 dB, and very loud sounds like a rock concert or a jet engine reaching levels above 100 dB. Extremely high-intensity sounds can be harmful to human hearing.
It's worth noting that while the human hearing range is commonly referenced, many animals can hear frequencies beyond the human range. For example, dogs can often hear frequencies up to 40,000 Hz or higher.