Chapter 7

Question 1

What is a periodic back-and-forth motion (or oscillation) that transmits energy?

Answer 1

Wave

Question 2

What is the substance through which a wave transfers its energy?

Answer 2

Medium

Question 3

What are the high points of a wave train?

Answer 3

Crest

Question 4

What are the low points of a wave train?

Answer 4

Troughs

Question 5

What are waves in which particles of the transmitting medium oscillate at right angles to the direction of wave travel?

Answer 5

Transverse Waves

Question 6

What are waves in which the particles of the transmitting medium oscillate in the direction of wave motion?

Answer 6

Longitudinal Waves

Question 7

What is the term for the squeezed portion of the coils of the spring?

Answer 7

Compression pulse

Question 8

What is the term for the portion of the spring where the coils are spread out?

Answer 8

Rarefaction pulse

Question 9

What is the length of a single wave?

Answer 9

Wavelength

Question 10

What Greek letter represents wavelength?

Answer 10

Lambda (looks similar to a wishbone)

Question 11

What is the term for the number of waves that pass a given point per unit time

Answer 11

Frequency

Question 12

What is the SI unit of frequency?

Answer 12

Hertz

Question 13

What is the time needed for one cycle of wave to pass?

Answer 13

Period

Question 14

Formula for Period

Answer 14

Period = Time/Waves = 1/Frequency

Question 15

Formula for Frequency

Answer 15

f = Waves/Time

Question 16

What is the rate at which a wave travels through a medium?

Answer 16

Speed

Question 17

Formula for Speed of a Wave

Answer 17

v = Lambda(f)

Question 18

What is the change in the course of a wave as a result of a collision with an object of boundary?

Answer 18

Reflection

Question 19

What states that the angle of incidence equals the angle of reflection?

Answer 19

Law of reflection

Question 20

What is the bending of the path of a wave as a result of a change in wave speed?

Answer 20

Refraction

Question 21

What is the spreading out of a wave after it passes through a narrow opening?

Answer 21

Diffraction

Question 22

What is the reinforcement or cancellation that occurs when two or more waves meet?

Answer 22

Interference

Question 23

What is the term for vibrations traveling through a medium in the form of longitudinal pressure waves?

Answer 23

Sound

Question 24

What is the strength of a sound wave?

Answer 24

Intensity

Question 25

What is the effect of intensity on the way the human ear perceives sound?

Answer 25

Loudness

Question 26

What is the measurement used for sound intensity level?

Answer 26

Decibel

Question 27

What is the effect of frequency on the way the human ear perceives sound?

Answer 27

Pitch

Question 28

What is sound that can be heard?

Answer 28

Audible sound

Question 29

What are sounds with pitches below the audible range?

Answer 29

Infrasonic sounds

Question 30

What are sounds above the audible range?

Answer 30

Ultrasonic sounds

Question 31

What is the change in frequency caused by object's motion?

Answer 31

Doppler effect

Question 32

What is the main factor affecting the speed of sound in air?

Answer 32

Temperature of air

Question 33

What is a violent compression pulse caused by constructive interference?

Answer 33

Shock wave

Question 34

What is the loud noise that sounds when a shock wave hits the ear?

Answer 34

Sonic boom

Question 35

What are the multiple reflections that cause the persistence of sound?

Answer 35

Reverberation

Question 36

What is a sound heard distinctly after being reflected from some object?

Answer 36

Echo

Question 37

What system, developed during WWII to locate submerged enemy submarines, emits sound waves underwater and analyzes the echoes reflected from submerged objects?

Answer 37

SONAR (SOund NAvigation & Ranging)

Question 38

What is the procedure for calculating distance by measuring the time interval that elapses between the sending of a sound wave and the return of an echo?

Answer 38

Echo ranging

Question 39

What is the process of dissipating the energy of sound waves?

Answer 39

Absorption

Question 40

What is the study of sound?

Answer 40

Acoustics

Question 41

What is a series of organized sounds waves with specific pitches that have been deliberately arranged?

Answer 41

Music

Question 42

What is random sound with no intended pattern?

Answer 42

Noise

Question 43

What is a definite pitch produced by a singing voice or musical instrument?

Answer 43

Note

Question 44

What is the difference in pitch between one note and a second note that is twice the frequency of the first?

Answer 44

Octave

Question 45

What is the result of two notes interfering harmoniously?

Answer 45

Consonance

Question 46

What are two notes that interfere in a more disagreeable way?

Answer 46

Dissonance

Question 47

What is the distance between two notes?

Answer 47

Interval

Question 48

What is the burst of louder sound that rapidly fades in and out?

Answer 48

Beat

Question 49

What is the most dominant sound within a single note?

Answer 49

Fundamental

Question 50

What are the other sounds produced at higher frequencies than the fundamental?

Answer 50

Overtones

Question 51

What describes the frequency relationships between the fundamental and overtones?

Answer 51

Harmonic series

Question 52

What is the distinct sound quality of each musical instrument or voice?

Answer 52

Timbre

Question 53

What is the set of natural frequencies at which an object vibrates?

Answer 53

Natural Frequencies

Question 54

What is the state in which two frequencies are the same or nearly the same?

Answer 54

Resonance

Question 55

What reverberates the sound waves produced by the instrument to make the sound louder by resonance?

Answer 55

Resonator