Speech and Hearing Exam 1

MKS system

meter, kilogram, second

what is a newton

kg X m/s²

displacement is

length or distance with a direction

quantity can be fully described by magnitude (e.g., size,

amount, length

scalar

quantity has both magnitude and direction

vector

is the vector equivalent of speed

velocity

formula for velocity and its unit

v= displacement/ time m/s

the change in velocity over time

acceleration is a vector

formula for acceleration unit

a= v/t m/s²

formula for force unit

F= Ma newtons

is defined as force divided by the area over which it is applied.

pressure

formula for pressure and units

p=F/A pascals

power =

pressure²

All three quantities (pressure, power, intensity) can

be used to describe the

amplitude

The property that makes a deformed object return to its original shape is called

elasticity or stiffness

The force that opposes the deformation of

an elastic material is called the

restoring force

When one object rubs against another

object, the force that opposes the motion is

called

friction

Vibration is the back-and-forth motion of an object,

also referred to as

oscillation

The simplest form of sound vibration is produced by

simple harmonic motion

A characteristic of simple harmonic motion (SHM) is that the ________ of the oscillations stays ________

timing and constant

The dying out of oscillations over time is called

damping

Speed of sound in air

344 m/s

The outward movement of the tines causes some

air molecules to _____ and leads to an _________ in pressure

compressed increase

When the tines return to equilibrium, the force on

the air molecules _________ and leads to a ________ in pressure

rarefaction decrease

describes a relationship between displacement and time

Sine Wave

left and right moving wave

longitudinal

Up and down moving wave

transverse

Waves start at what degrees then move into ….

0, 90, 180, 270, 360 or 0

How many times an object moves back and forth

(vibrates) every second.

frequency cycles per sec = hz

How far an object moves (magnitude of displacement)

from resting point.

amplitude

Time it takes for one complete

cycle of vibration.

period

if frequnect is 100Hz what is period

0.01s

Distance between any two identical points on a sine

wave

wavelength

Wavelength formulas

Wavelength = 344m/s times period or 344m/s/force

combination of two or more pure tones

complex wave

repeat a pattern over time

periodic wave

do not repeat a pattern over time

aperiodic wave

lowest frequency component of a complex periodic wave

fundamental frequency

integer (whole number) multiple of the fundamental frequency

harmonic

If the fundamental is 200 Hz, then harmonic 3 (H3) is

600Hz

a graph of amplitude (y-axis) as a function of frequency (x-axis) graph that is lines going straight up

spectrum

brief abrupt sound

transient

many frequency components, all with

same amplitude

white noise

place of zero displacement in the standing wave

nodes

place of maximum displacement in

the standing wave

antinodes

Node at each end and antinode in the

center

first mode

opposition to flow of sound energy

impendence

ease of sound flow

admittance

Increasing frequency will ________ stiffness

reactance whihc opposes ______ frequencies more

decrease low

Unit for Intensity.

decibel

Add 2nd sound of same level, how much does dB IL and SPL

increase?

IL- 3dB SPL- 6dB

opposes high frequency vibrations

mass

opposes low frequency vibrations

stiffness

mass + stiffness equals

resonant frequency

point where opposition to vibration caused by mass or stiffness is the lowest

resonant frequency

object itsself is set into vibration

mechanical resonator

container filled with air that act as a resonator

acoustic

how far the wave spreads outwards

bandwidth

point at which the resonant system is considered to be unresponsive, and intensity is reduced by 1/2

cut off frequency