Speech and Hearing Sci - Chapter TWO Motion

Describing and Explaining Motion

Speeh is movement made…

audible

speech requires what systems?

neural, respiratory, phonatory, resonatory, atrticulatory, auditiory systems

sound wave is a disturbance that…

propagates energy via a medium.

ex: in water will be different than in air

velocity

speed (distance travelled in a a given unit of time

acceleration

rate of change of velocity

how speech production include velocity

velocity of mandibular closure

velocity of apical tongue movement

..think of tone, cadence

laws of motion (first)

• object in motion stays in motion unless acted upon by an external force

this tendency to resist chance in a state of motion is inertia.

law of motion (second)

acceleration of an object occurs in the same direction as the net force and is inversely porportional to the mass of the object

F=M * A

in terms of speech:

movement of the tongue for trill /r/

heavy tongue vs lighter tongue

law of motion (third)

with every action there is an equal and opposite reaction

in terms of speech:

opening/closing of VF

EX: VF '“snapping back” after subglottal pressure

momentum

quantity of motion measure as a product of mass and velocity

force of subglottall pressure is higher initally because the momentum carries out the vibration once the minimum is reached.

energy is

ability to do work

displacement caused by the application of force

potential vs kinetic energy

in terms of speech the effort require to move an articulator. energy transfer is ESSENTIAL. total energy does not change unless there is friction.

person 20 ft away from you has a lot of friction. energy is lost=sound is less.

states of matter in terms of speech

air molecules can change speech perception.

normal air, vs sauna vs underwater. EFFECTS VELOCITY OF SOUND

air molecules in vocal tract collide against each other EFFECTS DENSITY

air/pressure in terms of speech

air molecu exert force on the walls of the vocal tract

pressure- force per unit area. air pressure in different locations are almost equal. **think subglottal presssure, atomspheric pressure, etc

stifness

degree to which an object resists being deformed

elasticity

ability of an object to return to its resting shape once forces are removed

what is sound

pressure wave

• regions of high and low pressure. audible to human ear

  • speech is composed of sound waves. sound waves are vibrations of particles

total energy remains the same under what conditions

no friction!!

in reality - frictional forces are always present. energy will be reduced every successive cycle of vibration or oscillation

EXCEPTION:

presence of external forces that continues to provide energy

mechanical waves(aka sound) require a ___

medium.

remember! characteristics of medium affect the speed of propagation.

what would be a single disturbance

pulse, pulse wave

what is a transverse wave

up and down; perpendicular

Think of a stadium wave

what is a longitudinal wave

direction of movement of particles in the medium is PARALLEL to the direction of the wave

this is how sound waves travel

think of a wave pool, left to right

high pressure in a wave are

COMPRESSIONS - regions of increased density and air pressure

low pressure in a wave

RAREFACTIONS - regions of decreased density and air pressure a

a sinusoidal wave or sine wave is a

series of simple oscillations/vibrations W/O friction

what are waveform axises

x axis = time

y axis = amplitude (pressure) remember high/low

four terms describing a wave

• frequency/phase - # of cycles of vibration PER SECOND

• period - time between successive points of low or high pressure T= 1/f

• wavelength - distance traveled by one cycle of vibration. wavelen = c/f. c is velocity f is freq.

• intensity - amount of energy transferred from one particle to next. intensity = power/ area. this depends on the amplitude of displacement of particles

IN PHASE

Beginning matches the end.

amplitude reduce with…

distancee from the source of sound

*sound intentisy is relative measure i

intenstiy is propotional to

AREA

speech intensity is measured in —-. why?

dB SPL.

range of hearing is too large to use traditional measure of WAtts per meter sq.

unit of loudness

phon

loudness doubles per 10 phons

intensitys physiological correlates to

loudness

human ear notices chnages better at

lower frequencies

freq psychological sorrelate to

pitch

a 10 hz pure tone implies that there are __ vibration cycles per 10 seconds.

100!

10 hz × 10 seconds = 100

amplitude increases as the sq of the intensity. t/f

FALSE

pure tone

result of vibration at single freq

simple harmonicc

complex tone

result of vibrations at two or more frequencies

• the 2 lower waves combine to make the top wave. lowest f is f0.

if there is a mathematical relationship IN A COMPLEX WAVE between each period between (for an example) 100hz 200 hz 300hz etc then…..

its not just a complex wave it is a complex periodic wave

2 spectrums

a spectrum is a representation of frequency on the x axis and amplitude on the y axis.

1. line spectrum - bar graph that represents the nergy at one point in time

2. continuous spectrum - no pattern, aperiodic. tbh a mess

aperiodic sound

• no periodicity

• no arithmetic relationship

• most natural sound

  • SPEECH

a continuous [power spectrum is best used to represent ___.

NOISE

Constructive vs Destructive Interference

con- superimposed, same freq but higher amplicity.

des- OUT OF PHASE. combined= no movement.

in/out phase is crucial

complex interference

amplitude is compounded on AND negated.

how do sound waves change behvaiors

boundaries - from water to air

reflection- echo? incident wave

diffraction - sound wave bends arond obstacle

transmission - sound wave go thru boundary

speech is primarily reflection and transmissionre

resonance

phenomenon that explains the ease with objects are set into vibration.

standing waves - a type of interfernece by the ___ and __ wave. this causes

incident and reflective wave

this causes resonant patterns

**think of whiping a string up and down.

standing waves have

nodes and anti nodes

points of no movement = nodes!!!!!

max movement = antinodes

**complex tones have multiple standing waves

what does a forced vibration do to a wave (in temrs of resonance)

one medium vibrates away from the natural resonant frequency this leads to reduced displacement/amplitude. t

this behavior of sound waves is responsible for standing waves

reflection

when the amplitude of a sound wave doubles the intensity is halved. T/F

False.

Amplitude doubles = intensity doubles.

wavelength equation

wavelength = velocity of sound / frequency of sound

wavelength is what distance

distance travelled of one cycle of vibration

wavelength increases, frequency ____

decreases

when you superimpose a wavelength with same '“start” does the frequency double or stay the same

stays the same .

amplitude increases