SAT VOCAB TWO - PowerPoint Presentation

Slide1

SAT VOCAB TWO

Audible (

adj.)

able to be heard

Oscillate

(v.)

to sway from one side to another

Dissonance (

n.)

lack or harmony or consistency

Undulate (

v.)

to move in wavesSlide2

SAT VOCAB TWO

Now that we are through with waves, we are moving onto the topic of sound. Sound waves are waves that are

_______________.

The reason we can hear them is that the waves make

our

ear drum

___________________

because the wave

_______________

in the ear canal. When we hear something that is

not

of a pleasing

quality, it

creates

________________

and we think of it as noise.Slide3

Sound

Chapter 12Slide4

REVIEW

Waves

transport

ENERGY, not matter.

Waves are mechanical (matter) or non-mechanical (no matter).

Sound is mechanical.

Light is non-mechanical.

Transmission of SoundSlide5

SOUND WAVES

Sound

waves

are

Compressional

waves.

The vibrations of the molecules are parallel to the direction of the wave.

Produced by the

compressions

and rarefactions of matter.Slide6

SOUND WAVES

Sound is produced by a

vibrating

object

.

As one individual particle is disturbed, it

transmits the disturbance

to the next interconnected particle.

This disturbance continues to be passed on to the next particle. The result is that energy is transported without the actual transport of matter.Slide7

SOUND WAVES

LABEL YOUR DIAGRAMSlide8

SOUND WAVESSlide9

WHAT DO SOUND WAVES LOOK LIKE

Visualizing SoundSlide10

SPEED OF SOUND

Speed depends upon how fast one particle can

transfer its motion

to another particle.

Speed of sound depends on the

Elasticity

Medium (Density)

Temperature

Why?

Sonic boomSlide11

SPEED OF SOUND

Speed of Sound

: depends on the

elasticity, density and temperature.

Elasticity

– the ability of an object to

bounce back to its original shape. Sound travels

faster

in more elastic objects. Typically gases are the

least elastic, liquids are next and solids are the most elastic.Density – generally speaking, in material of the same state of matter (solid, liquid or gas) the

denser

the medium the

slower

the sound travels. Sound travels slower in

lead than it does in

steel

.

Temperature

– generally speaking the

higher the temperature,

the

faster

the speed of sound.Slide12

SPEED OF SOUND

Speed of Sound – on

average

Air is 767 mph

(346

m/s) – about

1 mile per 5s. Water is 3,315 mph

(

1,482 m/s

) about 1 mile per 1.1s.Steel is 13,330 mph (5,960m/s) about 1 mile per 0.27s or 3.7mile per 1s.Slide13

SPEED OF SOUNDSlide14

SPEED OF SOUNDSlide15

BREAKING THE SOUND BARRIER

Chuck Yeager

–

first man to fly faster than the speed of sound

Andy Green

–

first man to drive a land vehicle faster than the speed of sound.

October 14, 1947 –

in X1 “Glamorous

Glennis

”

October 15, 1997 –

in

SuperSonic

Car

“Thrust SSC”

763 MPHSlide16

HOW WE HEARSlide17

HOW WE HEAR

When a sound wave reaches the ear, a series of

high and low pressure regions

hit the eardrum.

The arrival of a

compression

or high pressure region pushes the eardrum inward; the arrival of a

low

pressure

region serves to “pull” the eardrum outward. The continuous arrival of high and low pressure regions sets the eardrum into motion. Slide18

HOW WE HEAR

Auricle (Pinna-the

ear flap)

–

used to focus the sound waves into the ear canal

Ear Canal (

Auditory Canal

)

–

focuses the sound onto the ear drum.Ear Drum (Tympanic membrane) – Sound

starts the ear drum vibrating.Slide19

HOW WE HEAR

Ear Drum

vibrates

Three smallest

bones

vibrate

, one after the nextHammer (Malleus) is

touching the ear drum & vibrates

first.

Next is the Anvil (Incus). Last is the Stirrup (Stapes).

Eustachian Tube

:

tube that connects the middle ear

with

the

throat.

This allows the pressure on both sides of the ear drum to equalize.Slide20

HOW WE HEAR

The

Stirrup

vibrates the

oval window

of the cochlea. Cochlea

is a

long fluid filled tube, folded in half and thencoiled up like a snail shell. The entire inner surface is lined with cilia, little hairs. Once cilia are vibrated

, the attached

nerves

are stimulated & send signal

to

the brain.

Balance

is achieved by the

semicircular

canals

.

Three

canals

in

t

hree

different planes are able to determine

the body’s

position in space

.Slide21

HOW WE HEAR

Need to know these structures & their function: Outer Ear, Middle Ear, Inner Ear,

Auricle, Ear

canal, E

ar drum, Hammer, Anvil, Stirrup,

Oval Window, Cochlea, Auditory Nerve, Semicircular Canals, Eustachian

Tube.Slide22

PROPERTIES OF SOUND

Intensity

–

the amount of

energy

the wave carries; sound level is measured in decibels (dB

);

it influences how far away a sound can be heard.Slide23
Slide24

PROPERTIES OF SOUND

Loudness

– how we perceive

intensity.

depends

on the

amplitude.

Larger

amplitude

means more pressure.Remember: amplitude is a measure of the amount of energy in the wave.Slide25

PROPERTIES OF SOUNDSlide26

PROPERTIES OF SOUND

Frequency

– the number of

wavelengths

that pass a particular point (vibrations) per

second

, Hz.Human Hearing – between 20 Hz – 20,000 Hz.Below 20 Hz is called

infrasound.

Above 20,000 Hz is called

ultrasound.Pitch - determined by frequency; the highness or lowness of sound. high frequency yields

high

pitch sounds

Low

frequency yields

low

pitchSlide27

PROPERTIES OF SOUND

Resonance

– when the

frequency

of sound matches the

natural frequency

of an object.

Low Pitch

High Pitch

Low to High Frequency

Pitch and FrequencySlide28

TACOMA NARROWS BRIDGE COLLAPSE

Nov. 7, 1940

Galloping

Gertie

On a day of rather high winds, Gertie took on a 30-hertz

transverse

vibration (like sending waves down a rope by moving the end up and down) with an amplitude of 1½

feet!

It later took on a twisting motion of about 14 hertz and quickly tore itself in two. Slide29

PROPERTIES OF SOUND

Sound waves can be

reflected

.

A

reverberation

is perceived when the reflected sound wave reaches your ear in less than

0.1 second

after the original sound wave

.An echo takes longer.Slide30

PROPERTIES OF SOUND

Doppler

e

ffect

Variation

in the perceived

pitch

of a sound due to a

moving

sound source.“bunches up” in front of the sourceSpreads out behind the sourceSlide31

Doppler Effect

PROPERTIES OF SOUNDSlide32

A

sonic boom

is the sudden onset and release of

pressure

after the buildup by

a sound

shock wave

.

Sonic Boom

PROPERTIES OF SOUNDSlide33
Slide34
Slide35

This picture shows a sonic boom created by the THRUST SSC team car as it broke the land speed record

and broke the

sound

barrier on land. Slide36

MUSIC VS NOISE

Music

is sounds that are deliberately used in a

repeated pattern

.

Noise

has random patterns and pitches.

Sound ApplicationsSlide37

MUSIC VS NOISE

Materials have their own

natural frequencies.

Examples:

guitar strings, wine glass, other musical

instruments

Resonance is the ability of an object to vibrate by absorbing energy at its

natural frequency

.

Wine glassesSlide38

USING SOUND

Acoustics

is the study of

sound

.

Sound is studied so that concert halls, classrooms, theaters, etc. can be constructed to minimize

destructive interference and diffuse reflection.Slide39

ECHOLOCATION

The

use

of sound waves and echoes to determine where objects are in

space.

Bats

send out sound waves using their mouth or

nose

.  

When the sound hits an object, an echo comes back.They can tell the distance between themselves and the object

.

They can identify an object by the

sound

of the echo.Slide40

ECHOLOCATION

They can even tell the

size, shape and texture

of  a tiny insect from its echo.  

Most bats use echolocation to 

navigate

in the dark and find

food

.

VIDEOSlide41

SONAR

Sonar - Sound Navigation and Ranging

Sonar uses sound waves to

'see'

in the

water

It is

helpful for

exploring

and

mapping

the ocean because sound waves travel

farther

in the water than do radar and light waves.Slide42

ULTRASOUND

a

device that uses

high

frequency sound waves to create an

image

of some part of the inside of the body, such as the stomach, liver, heart, tendons, muscles, joints and blood vessels.Slide43

BIOACOUSTICS

Bioacoustics

is

a branch of science concerned with the

production of sound

and its effects on

living systems.Animals that generate

infrasound

include elephants, whales, alligators, hippos, rhinos, giraffe, lions, tigers and several birds. Animals that generate ultrasound include dolphins, bats, many birds and insects. Slide44

CYMATICS

from Greek

meaning

“wave”.

Typically a

surface is vibrated and regions of maximum and minimum displacement are made visible in a thin coating of particles, paste or liquid.

Different

patterns

emerge as the surface vibrates.Cymatics