Definitions

Front 1

Sound

Back 1

a disturbance in an elastic medium that propagates through the medium as longitudinal wave motion/stimulus that causes an auditory sensation

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medium

Back 2

substance that occupies a space; can be a solid fluid or gas

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density

Back 3

mas per unit volume

Front 4

density is determined by

Back 4

mass of the individual particles and the spacing of the particles

Front 5

Air pressure/atmospheric pressure

Back 5

a result of the weight of the atmosphere (air molecules) acting on a specific surface

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compression

Back 6

positive air pressure change

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rarefraction

Back 7

negative air pressure change

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waveform

Back 8

function representing changes of any physical quantity as a function of time

represents changes of any physical quantity as a function of time

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X/Y axis of a waveform

Back 9

x axis= time
y axis= displacement/velocity/acceleration

Front 10

monopole

Back 10

source which radiates sound equally well in all directions

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wave

Back 11

disturbance of a medium which transports energy through the medium without permanently transporting matter

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frequency

Back 12

rate of vibration
# of cycles per second

Front 13

magnitude

Back 13

an amount or quantity of something

Front 14

vibration/oscillation

Back 14

back and forth motion around an equlibrium position

due to force of elasticity

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pendulum swings back and forth due to

Back 15

interaction between inertia and the restoring force of gravity

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sinusoidal motion

Back 16

oscillation made by pendulum is sine function

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periodic motion

Back 17

motion that repeats itself in regular intervals until it is stopped by external action

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simple harmonic motion

Back 18

form of back and forth motion that produces a pure tone

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pure tone

Back 19

one frequency of vibration

Front 20

period

Back 20

time required for completion of one cycle of a periodic motion

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wavelength

Back 21

the physical distance in space occupied by one period of a wave

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phase

Back 22

indicates a particular stage in the cycle of motion using the angles from a circle as the unit of measure

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propagating wave

Back 23

energy moving through a medium

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intensity

Back 24

determines the degree to which the density of the air changes

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particle velocity

Back 25

the velocity of the particles in the medium

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sound pressure indicates

Back 26

how compressed or rarefied the particles are, which is related to the density of the particles in the medium

Front 27

sound intensity indicates

Back 27

how much sound power is transferred from the sound source to the surrounding area

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sound intensity is proportional to

Back 28

the square of sound pressure

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watt

Back 29

the ability of a system to do 1 joule of work in one second

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joule

Back 30

the amount of work done when 1kg mass is moved 1 meter

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energy

Back 31

stored in an object and is gradually expended when the object does work

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power

Back 32

the rate at which a system is gaining or loosing energy

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work

Back 33

the force required to move some mass some distance

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energy

Back 34

ability or capacity of an object to do work

the force required to move some has some distance in some amount of time

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kinetic energy

Back 35

energy that some object possesses due to its velocity

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force

Back 36

push or pull, an interaction between 2 objects or an object its environment

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friction

Back 37

when an object or substance moves across or throughout another substance, this rubbing together impedes or opposes the movement of the object

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inertia

Back 38

objects at rest stay at rest, objects in motion stay in motion. resistance of a body to changes in its motion

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elasticity

Back 39

ability to resist changing shape

property of a substance that resists its compression, substance wants to remain or return to its original density

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mass

Back 40

amount of matter present in a substance

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newton's 1st law

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an object at rest will remain at rest and an object in motion will remain in motion and move with uniform velocity unless acted upon by an external force

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newton's 2nd law

Back 42

an object's acceleration is proportional to the foce exerted on the object and inversely proportional to the mass of the object

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acceleration

Back 43

the rate of change in velocity

Front 44

displacement

Back 44

change in postion (m)

distance from the original position to the final position

Front 45

velocity

Back 45

rate of displacement (m/s)

Front 46

instantaneous magnitude

Back 46

the magnitude of a waveform at any given moment of time

Front 47

amplitude

Back 47

maximum magnitude

Front 48

phase relationship

Back 48

difference between the phases of two periodic waveforms as they cycle through time

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in phase

Back 49

when 2 waveforms have the same frequency and the same phase

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out of phase

Back 50

2 waveforms have the same frequency but the phase is not the same

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to determine if it is possible to describe the phase relationship when 2 waveforms are not of the same frequency

Back 51

1. the higher frequency is an integer multiple of the lower frequency
2. the higher frequency is not an integer multiple of the lower frequency

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complex vibrations

Back 52

created by the combination of 2 or more sinusoidal vibrations

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components

Back 53

the sinusoidal vibrations that make up complex vibrations

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fourier theorem

Back 54

any complex vibrations is the sum of various sinusoidal motions of varying amplitude, frequency, and phase

Front 55

waveform synthesis

Back 55

instantaneous mag. of complex waveform can be determined by adding the instantaneous mags. of components

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periodic vibration

Back 56

has a clearly repeating pattern

Front 57

aperiodic vibration

Back 57

motion is random (noise)

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fundamental frequency

Back 58

1st harmonic

inverse of fundamental period

Front 59

fundamental period

Back 59

duration of one cycle

Front 60

spectrum

Back 60

different type of graph that is used to show the amplitude to the components

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x/y axis for spectrum

Back 61

y axis= amplitude of the sinusoidal wave

x axis= frequency

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sawtooth wave

Back 62

has spectral components that include all whole number multiples of the fundamental frequency with decreasing amplitude

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square wave

Back 63

has spectral components that include all odd-number multiples of fundamental frequency with decreasing amplitude

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triangular wave

Back 64

has spectral components similar to a square wave, but amplitude decreases quickly

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spectrum with 1 or more vertical lines

Back 65

line spectrum/discrete spectrum

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spectrum with many spectral components

Back 66

continuous spectrum

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membrane

Back 67

thin sheetlike material stretched and fixed along its edges. membranes can be flat like a drum or curved like a loudspeaker cone

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plate

Back 68

has is own stiffness and can vibrate without any structured support. plates can be flat (somewhat like a cymbal) or curved (like a bell)

Front 69

characteristics of object that determine characteristics of a propagating sound wave

Back 69

frequency and magnitude