Theory:

How do we hear sound?
  
Sounds generated by the different sources reach our ear by travelling through the air.
Structure of Human ear:
The ear is the organ of the human body that enables us to hear different sounds around us. The ear can be divided into three main parts:
  • Outer ear
  • Middle ear
  • Inner ear
Anatomy_of_the_Human_Ear.svg.png
Structure of human ear
Outer ear:
  • This is the outermost visible part of the human ear.
  • The outer ear gathers sound waves and forwards them towards the ear canal.
  • At the end of the ear canal lies the eardrum. Sound waves travel through the ear canal and strike the eardrum.
ear-anatomy-human-medical-left-42411 (1).svg
Outer ear  
Middle ear:
  • The eardrum is made up of a membrane, which starts vibrating with the frequency of the sound wave that falls on it and, it converts the sound waves into vibrations that then travel to the inner ear.
  • The eardrum is a thin rubber like sheet present in the Middle ear.
  • when the sound waves reach the eardrum, the eardrum vibrates and these vibrations propagate to the inner ear.
900px-Blausen_0330_EarAnatomy_MiddleEar.png
Middle ear
Inner ear (Cochlea):
  • Inner ear(cochlea) receives the vibrations sent by the eardrum.
  • The inner ear contains a liquid-like substance through which the vibrations can travel.
  • The inner ear has some tiny hairs that turn the vibrations into signals. The brain receives the signals through the hearing nerve.
  • When the brain receives the signal, it interprets the sound instantaneously. However, the whole process is so quick that we cannot notice it.
Reference:
https://commons.wikimedia.org/wiki/File:Anatomy_of_the_Human_Ear.svg
https://snappygoat.com/s/?q=bestof%3Ahearing+ear+ears+music+headphones+listen+head+anatomy+medical+model+skull+cutaway+body+otolaryngologist+doctor+noise+noise+damage+tympanic+membrane+anvil#5ed1203a4fe3f34e3f399ac60532310a1b38e54c,0,815.
https://commons.wikimedia.org/wiki/File:Blausen_0330_EarAnatomy_MiddleEar.png