Test 1

Question 1

vibration

Answer 1

periodic wiggle in time

Question 2

wave

Answer 2

a periodic wiggle in both space and time

Question 3

what kind of wave is a sound wave?

Answer 3

mechanical

Question 4

sine curve

Answer 4

pictorial representation of a wave produced by simple harmonic motion

Question 5

amplitude

Answer 5

distance from the midpoint to the crest of the wave

Question 6

wavelength

Answer 6

distance from the top of one crest to the top of the next crest

Question 7

frequency

Answer 7

how frequently a vibration occurs

Question 8

what is the unit of frequency

Answer 8

the hertz

Question 9

period

Answer 9

time for one complete vibration

Question 10

how are frequency and periods related mathematically?

Answer 10

they are reciprocals

Question 11

frequency =

Answer 11

1/period

Question 12

period =

Answer 12

1/frequency

Question 13

transverse wave

Answer 13

the motion of the medium is transverse to the direction the wave travels

Question 14

transverse motion

Answer 14

the right-angled, or sideways, motion of a wave

Question 15

longitudinal wave

Answer 15

the motion is along the direction of the wave rather than at right angles to it

Question 16

wave speed =

Answer 16

frequency x wavelength

Question 17

wave interference

Answer 17

when two waves overlap each other

Question 18

interference pattern

Answer 18

• overlapping of waves

- wave effects may be increased, decreased or neutralized

Question 19

superposition principle

Answer 19

when more than one wave occupies the same space at the same time, the displacements add at every point

Question 20

constructive interference

Answer 20

when the crest of one wave overlaps the crest of another and their individual effects add together to produce a wave of increased amplitude

Question 21

destructive interference

Answer 21

when the crest of one wave overlaps the trough of another, their individual effects are reduced. the high part of one wave fills in the low part of another

Question 22

standing wave

Answer 22

a stationary interference pattern formed in a medium when the two sets of identical waves pass through the medium in opposite directions

Question 23

Doppler effect

Answer 23

the shift in received frequency due to the motion of a vibrating source toward or away from a receiver

Question 24

bow wave

Answer 24

the v-shaped disturbance created by an objet moving across a liquid surface at a speed greater than the wave speed

Question 25

shock wave

Answer 25

the cone-shaped disturbance created by an object moving at supersonic speed through a fluid

Question 26

sonic boom

Answer 26

the loud sound that results from the incidence of a shock wave

Question 27

pitch

Answer 27

the highness or lowness of a tone; related to wave frequency

Question 28

infrasonic

Answer 28

describes a sound that has a frequency too low to be hear by the normal human ear

Question 29

ultrasonic

Answer 29

describes a sound that has a frequency too high to be heard by the normal human ear

Question 30

compression

Answer 30

a condensed region of the medium through which a longitudinal wave travels

Question 31

rarefaction

Answer 31

a rarefied region of the medium through which a longitudinal wave travels

Question 32

reverberation

Answer 32

the persistence of sound, as in an echo, due to multiple reflections

Question 33

refraction

Answer 33

the bending of sound or any wave caused by a difference in wave speeds

Question 34

forced vibration

Answer 34

the setting up of vibrations in an object by a vibrating force

Question 35

natural frequency

Answer 35

the frequency at which an elastic object tends to vibrate when it is disturbed and the disturbing force is removed

Question 36

resonance

Answer 36

the response of a body when a forcing frequency matches its natural frequency

Question 37

interference

Answer 37

a result of superposing different waves, often of the same wavelength. constructive interference results from crest-to-crest reinforcement; destructive interference results from crest-to-trough cancellation

Question 38

beats

Answer 38

a series of alternate reinforcements and cancellations produced by the interference of two waves of slightly different frequencies, heard as a throbbing effect in sound wave

Question 39

pitch

Answer 39

the highness or lowness of a tone, as on a musical scale, which is principally governed by frequency. a high-frequency vibrating source produces a sound of high pitch and vise versa

Question 40

intensity

Answer 40

the power per square meter carried by a sound wave, often measured in decibels

Question 41

loudness

Answer 41

the physiological sensation directly related to sound intensity or volume

Question 42

quality

Answer 42

the characteristic sound of a musical instrument or voice, which is governed by the number and relative intensities of partial tones

Question 43

partial tone

Answer 43

a single frequency component sound wave of a complex tone. when the frequency of a partial tone is an integer multiple of the lowest frequency, it is referred to as harmonic

Question 44

fundamental frequency

Answer 44

the lowest frequency of vibration, or first harmonic, in a musical tone

Question 45

harmonic

Answer 45

a partial tone whose frequency is an integer multiple of the fundamental frequency. the second harmonic has twice the frequency of the fundamental and the third has three times the frequency and so on

Question 46

fourier analysis

Answer 46

a mathematical method that disassembles any periodic waveform into a combination of simple sine waves