Unit 6 - Key Words Energy Transfers and Sound 2 Flashcards
movement back and forth - vibrations are sometimes referred to as oscillations
vibrate
a wave where the vibrations are parallel to the direction of energy transfer
longitudinal wave
a unit of sound loudness
decibel (dB)
the maximum displacement of a point on a wave from the undisturbed (equilibrium) position
amplitude
the number of waves passing a set point, or emitted by a source, in a second – frequency is measured in hertz (Hz or /s).
frequency
a graph of the displacement of wave motion, at different distances along the wave
waveform
the distance between two identical points on consecutive waves e.g. the distance from one crest to the next or one trough to the next
wavelength
a device for changing sound into an electrical signal
microphone
when a wave, such as light, bounces off a surface
reflection
the effect of hearing a sound twice once when it is created and the second time after the sound wave has undergone reflection before being heard.
echo
the speed at which a sound wave
speed of sound
the speed that a wave travels
wave speed
waves speed (m/s) = wavelength (m) × frequency (Hz)
a technique used to measure distance by detecting reflected ultrasound waves
sonar
a very small part of a material such as an atom or a molecule
particle
a space where there are no particles of matter
vacuum
an idea that explains facts or observations and is the basis for experimentation (X depends on Y)
hypothesis
to redirect a wave such as sound or light
reflect
to take in energy e.g. from sound
absorb
using materials that absorb sound
soundproofing
where sound waves enter the ear
ear canal
the membrane in the ear that transfers energy from sound waves to the inner ear
ear drum
tiny bones in the ear that amplify the vibrations of sound
ossicles
part of the inner ear where vibrations are changed to electrical signals
cochlea
the nerve that transmits signals from the ear to the brain
auditory nerve
a measure of the energy in a sound wave recorded in decibels (dB)
loudness
protection worn for the ears to protect them from loud sounds
ear defenders
the range of sound frequencies that an animal can hear
hearing range
