Nature of SoundNature of Sound

The speed of light in a vacuum is 299,792,458 meters per second or 186,000 miles per second (669,600,000 mph), which is roughly 870,000 times faster than the speed of sound.

CAN SOUND TRAVEL IN WATER?

IS THERE SOUND ON THE MOON?

• the sensation produced by stimulation of the organs of hearing by vibrations transmitted through the air or other medium

• Any sound that you hear as a tone is made of regular, evenly spaced waves of air molecules.NOISE

TONE

How is sound produced?• Vibration and particles of fluid• Source of sound Vibrations in

molecules in all directions ear eardrums

How is sound transmitted?• Through vibrations

• Travel in air, liquid, gas

• They do not travel in vacuum and so they do not travel in SPACE!

Speed of Sound Waves in Solids, Liquids and Gases

Speed in Solids > Speed in Liquids >

Speed in Gases

Why? This is because

molecules in a solid medium are much

closer together than those in a liquid or gas, allowing sound

waves to travel more quickly through it.

F A C T O R S A F F E C T I N F A C T O R S A F F E C T I N GG

W A V E S P E E DW A V E S P E E D

1.Properties of medium

1.1 Elastic properties – maintaining the object’s shape (no deformation) when force is applied.

- fastest in solids, then liquids and lastly in gases

1.2 Inertial properties – tendency to be lethargic in its state of motion

- includes mass and density

- sound will travel more faster in a less dense material than in a more dense material.

2. Properties of air, temperature and humidity

Speed of sound waves at different temperatures

• Higher Temperature = Faster sound waves

• Lower Temperature = Slower sound waves

Why? :/

• At lower temperatures the air is denser and therefore harder to travel through.

IMPORTANT USES OF IMPORTANT USES OF SOUNDSOUND

Important uses of SOUND• Ultra Sound tests

- diagnostic imaging techniques to create images of blood vessels, tissues and organs- Pregnant women -Aid detection of heart disease,

tumors, gallstones, etc

STETHOSCOPE-HEAR THE INTERNAL SOUNDS OF BODY.

-AMPLIFIES THE SOUND INSIDE YOUR BODY.

Thank You Thank You