Tag: study of sound

Let distance of hill from the position of the body = d
Echo is heard after 6 sec
$d = v \dfrac{t}{2}$
$= \dfrac{(340 \times 6)}{2}$
$= 1020 m$

Let $d$ be the distance of shack from the sonar . Therefore  distance covered by sound to come back to sonar after reflection from shack ,  $=d$ ,

If pitch is high frequency is high and vice versa.

Our inner ear is shaped like a snail and is called cochlea.

Combination of notes that produced jarring effect on the ear is called discord. Discord is lack of harmony between notes sounding together.

The sensation of hearing of any sound persists in our brain is 0.1 s. This is called the persistence of hearing. The persistence of hearing of human beings is not more than $\frac{1}{5}\,s$

The sound waves produces vibration of the ear drum and subsequently a forceful vibration of the bones of the middle ear. This high amplitude vibration is transmitted to the fluid of the inner ear and encoded in the nerve signal which is sent to the brain.

In order for us to be able to hear a sound at all, it has to be above a certain level. This level is called the auditory threshold or hearing threshold. Humans have a hearing threshold of around $0$ decibels. Above this threshold, sounds with higher sound pressure levels are heard as louder noises. Sounds above $90\, dB$ can lead to chronic hearing damage if people are exposed to them every day or all the time. Hearing becomes uncomfortable if the sound pressure level is above $110$ decibels (threshold of discomfort), and it becomes painful above $130$ decibels (threshold of pain).

Sound from the outside world are collected by pinna and reach the inner ear through auditory canal.

When the sound waves strike the eardrum or tympanic membrane it starts vibrating. Sound from the outside world are collected by pinna and reach the eardrum through auditory canal.