Sound waves are mechanical waves that require a medium for propagation. Let's learn about sound and more!
Sound is produced by a vibrating (the to and fro or back and forth motion of an object) body.
Vibrations that travel through the air or another medium and are audible when they reach a person's or animal's ear is sound.
In humans, the sound is produced by the voice box or the larynx (the vibrations of the vocal chords).
Sound is transmitted through a medium (gas, liquid, or solid). It will not be able to travel in a vacuum.
The eardrum detects sound waves. Vibrations are sent to the inner ear. The signal then travels to the brain. That's what we've heard.
Amplitude, Time Period, and Frequency of a Vibration
The amplitude of a vibrating body is defined as the largest extent of vibration from its mean position.
One oscillation is defined as a complete to and fro movement of the pendulum around its mean point. The time period is the amount of time it takes for a vibrating particle to complete one oscillation.
(i) Audible Sound: Humans can hear vibrations with a frequency of 20 Hz to 20,000 Hz (20 kHz).
(ii) Inaudible Sound: Sounds with frequencies greater than 20,000 Hz and less than 20 Hz are inaudible to the human ear.
Noise is a term used to describe sounds that are startling or unpleasant.
Musical sound is a type of sound that has a pleasant effect on the ear.
MEASURES TO LIMIT NOISE POLLUTION
Source: Chapter-13.pmd (ncert.nic.in)