Sound

• any object that vibrates produces sound
• sound wave travels on a medium
• sound waves travel through a solid faster than liquid, which is faster than through gas
• what are factors effecting the speed of sound?

  atmospheric pressure, relative humidity, atmospheric temperature
• pitch - a description of how high or low the sound seems to a person.
• loudness- how soft a sound is perceived to be.
• intensity - is the power carried by sound waves per unit area in a direction perpendicular to that area
• The outer ear - is a sound collector . The visible parts is shapes like a funnel
• middle ear - is the sound amplified.
• The middle ear is the sound amplified it consists of three tiny bones called the?

  Hammer, anvil and stirrup
• The inner ear - it contains a cochela .
• cochela - is filled with fluid and is lined with tiny hair like cells.
• Infrasound - sound bellow 20Hz it cannot be heard by the human ear but it can cause damage
• ultrasonic waves - above 20,000Hz cannot be detected by human ears but some animals do.