Physics Section 13-1: Sound Waves

Front 1

Sound waves begin with ___.

Back 1

A vibrating object.

Front 2

The vibrating prong of a tuning fork ___.

Back 2

Sets the air molecules near it in motion.

Front 3

Region of a longitudinal wave in which the density and pressure are greater than normal.

Back 3

Compression

Front 4

Region of a longitudinal wave in which the density and pressure are less than normal.

Back 4

Rarefaction

Front 5

Sound waves are ___.

Back 5

Longitudinal

Front 6

In a longitudinal wave, ___.

Back 6

Vibrations of air molecules are parallel to the direction of wave motion.

Front 7

(True/False) Audible waves are waves that humans can hear.

Back 7

True

Front 8

(True/False) Infrasonic waves have a higher frequency than audible waves.

Back 8

False

Front 9

Audible wave frequency range for an average human is:

Back 9

20 Hz - 20,000 Hz

Front 10

Ultrasonic waves are sound waves with frequency ___ than 20,000 Hz.

Back 10

Greater

Front 11

(True/False) Infrasonic waves can be used for medical imaging.

Back 11

False

Front 12

Ultrasonic waves have a ___ wavelength than audible waves.

Back 12

Shorter

Front 13

Different ___ can hear different ranges of sound.

Back 13

Species of life-form

Front 14

An individual's hearing depends upon ___.

Back 14

Age and exposure to loud noises.

Front 15

The perceived lowness or highness of a sound

Back 15

Pitch

Front 16

Pitch directly depends on ___.

Back 16

Frequency

Front 17

Higher pitched sounds have ___ frequencies.

Back 17

Higher

Front 18

Difference between frequency and pitch

Back 18

Frequency is objective because we can measure it; pitch is perceived.

Front 19

Ultrasonic waves have ___.

Back 19

Widespread medical applications.

Front 20

In order to produce images, sound waves must have a wavelength that is ___.

Back 20

As small as, or smaller than, the size of the object being measured.

Front 21

Sound waves are partially reflected when ___.

Back 21

They reach materials of different densities.

Front 22

The speed of sound depends upon ___.

Back 22

Medium's substance and its temperature.

Front 23

Sound waves can travel through ___.

Back 23

Solids, liquids, and gases.

Front 24

(True/False) Sound waves can travel through the vacuum of space.

Back 24

False

Front 25

Sound waves travel in ___.

Back 25

Three dimensions

Front 26

At distances far from the source, sound waves are ___.

Back 26

Plane waves.

Front 27

The Doppler Effect occurs whenever ___.

Back 27

There is relative motion between the source and observer of a sound.

Front 28

The pitch is higher ___ (in front of/behind) a source of sound.

Back 28

In front of

Front 29

As the frequency of a sound wave rises, ___ the pitch.

Back 29

So does

Front 30

Waves of frequency ___ MHz are typically used in medical imaging applications.

Back 30

10

Front 31

In the human body, sound travels at this speed.

Back 31

1500 m/s

Front 32

The higher the temperature of the medium, the ___ (faster/slower) the sound.

Back 32

Faster

Front 33

Rays are ___ to the wavefronts.

Back 33

Perpindicular

Front 34

A wavefront is ___.

Back 34

All the points on the same crest or trough in 3D space.