User:Richard and Kwasi

Ears and Hearing

Hearing is the sense that recives sound.Ears recive vibrations(sound waves) and change them into singnals.Sound is described by volume(how loud it is and by frequency).A normal conversation is about 65 decibles.Frequency is mesured in hertz.Most people can hear frequncies between about 16 and 20,000 hertz.Humans hear sounds when they pick up vibrations called sound waves.The vibrations enter your ear and hits the eardrum making a vibration that moves very small bones inside your skull.This sends a message along the auditory nerves to the brain.The brain makes sense of volume and frequncy and also registers them.When a human cannot hear the normal range of volume or frequency,he or she has hearing impairment.If a human cannot hear sounds below 90 desibles,the condition that this human is suffering is identified as deffness.