Waves and Sound Vocab

Question 1

Wave

Answer 1

A transfer of energy through matter or space

Question 2

Medium

Answer 2

The matter that waves travel through

Question 3

Transverse wave

Answer 3

Matter in the medium moves back and forth at right angles to the direction the wave is traveling
Ex. water waves, waves in a rope going up and down

Question 4

Longitudinal wave

Answer 4

Matter in the medium moves back and forth along the same direction the wave is traveling
Ex. sound waves

Question 5

Crest

Answer 5

Highest point of a wave

Question 6

Trough

Answer 6

Lowest point of a wave

Question 7

Frequency

Answer 7

The number of waves that pass a fixed point in one second, called a hertz

Question 8

Hertz

Answer 8

The unit of measurement for frequency. 1 Hz=1 wave per second

Question 9

Wavelength

Answer 9

The distance between crest to crest or a trough to a trough of a wave

Question 10

Rest position

Answer 10

The middle of a wave, between the crest and trough, the line of zero energy

Question 11

Amplitude

Answer 11

The height (or depth) from the crest (or trough) to the rest position, also called volume

Question 12

Volume

Answer 12

A measurement of loudness in a soundwave, measured in decibels

Question 13

Decibels

Answer 13

The unit of measurement for amplitude and volume “dB”

Question 14

Pitch

Answer 14

Hearing a low or high tone

Question 15

Doppler effect

Answer 15

A change in pitch (wave frequency) due to a moving sound (wave source)

Question 16

Resonance

Answer 16

When a material is made to vibrate by absorbing energy at its natural frequency

Question 17

Reflection

Answer 17

When a wave bounces off an object-mirror, echo, reflections

Question 18

Refraction

Answer 18

The bending of a wave caused by a change in its speed as it moves from one medium to another

Question 19

Natural frequency

Answer 19

The frequency that a uniform object vibrates the most at

Question 20

Diffraction

Answer 20

When waves bend around objects

Ex. hearing around a corner

Question 21

How would you describe how sound is emitted from a source, travels a distance, and is sensed by your ears

Answer 21

• sound waves are released
• vibrations move until they reach the ear
• eardrum then vibrates, causing a chain of vibrations the cochlea converts the sound waves

Question 22

Describe the noise of a passing train in a way that also describes the Doppler Effect

Answer 22

As the train gets closer, the pitch gets higher, as it goes away the pitch is lower

Question 23

How does a longitudinal wave through matter?

Answer 23

The sound waves in the beginning are larger, once it goes through the medium the waves are shorter.

Question 24

Describe how frequency and pitch are related

Answer 24

The frequency determines the pitch. The higher the frequency, the higher the pitch

Question 25

Draw a transverse wave with 3 crests/troughs, Label crest, trough, rest position, amplitude, and wavelength

Answer 25

• crest is the top
• trough is the bottom
• rest position is the dotted line, zero energy
• amplitude is the height (RP to crest or trough)
• wavelength is crest to crest or trough to trough

Question 26

Draw a longitudinal wave with 3 compressions and rarefactions. Label compression, rarefaction, and frequency.

Answer 26

• the denser part is the compression
• the lesser dense is the rarefaction
• the frequency is the distance from compression to compression or from rarefaction to rarefaction