Waves and Sound Vocab Flashcards
Wave
A transfer of energy through matter or space
Medium
The matter that waves travel through
Transverse wave
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
Longitudinal wave
Matter in the medium moves back and forth along the same direction the wave is traveling
Ex. sound waves
Crest
Highest point of a wave
Trough
Lowest point of a wave
Frequency
The number of waves that pass a fixed point in one second, called a hertz
Hertz
The unit of measurement for frequency. 1 Hz=1 wave per second
Wavelength
The distance between crest to crest or a trough to a trough of a wave
Rest position
The middle of a wave, between the crest and trough, the line of zero energy
Amplitude
The height (or depth) from the crest (or trough) to the rest position, also called volume
Volume
A measurement of loudness in a soundwave, measured in decibels
Decibels
The unit of measurement for amplitude and volume “dB”
Pitch
Hearing a low or high tone
Doppler effect
A change in pitch (wave frequency) due to a moving sound (wave source)
Resonance
When a material is made to vibrate by absorbing energy at its natural frequency
Reflection
When a wave bounces off an object-mirror, echo, reflections
Refraction
The bending of a wave caused by a change in its speed as it moves from one medium to another
Natural frequency
The frequency that a uniform object vibrates the most at
Diffraction
When waves bend around objects
Ex. hearing around a corner
How would you describe how sound is emitted from a source, travels a distance, and is sensed by your ears
- 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
Describe the noise of a passing train in a way that also describes the Doppler Effect
As the train gets closer, the pitch gets higher, as it goes away the pitch is lower
How does a longitudinal wave through matter?
The sound waves in the beginning are larger, once it goes through the medium the waves are shorter.
Describe how frequency and pitch are related
The frequency determines the pitch. The higher the frequency, the higher the pitch
Draw a transverse wave with 3 crests/troughs, Label crest, trough, rest position, amplitude, and wavelength
- 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
Draw a longitudinal wave with 3 compressions and rarefactions. Label compression, rarefaction, and frequency.
- 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
