Sound

• Amplifier


  A device for making a sound louder
• Amplify


  To increase the amplitude of a sound so that it sounds louder
• Amplitude


  The distance from the middle to the top or bottom of a wave
• Audible range


  The range of frequencies that you can hear
• Auditory canal


  The passage in the ear from the outer ear to the ear drum
• Auditory nerve


  An electrical signal travels along the auditory nerve to the brain
• Cochlea


  Snail-shaped tube in the inner ear with the sensory cells that detect sound
• Compression


  The part of a longitudinal wave where the air particles are close together
• Crest


  The top of a wave
• Decibel


  A commonly used unit of sound intensity or loudness (dB)
• Diaphragm


  The part of the microphone that vibrates when a sound wave hits it
• Ear


  The organ of the body that detects sound
• Eardrum


  A membrane that transmits sound vibrations from the outer ear to the middle ear
• Echo


  A reflection of a sound wave by an object
• Energy


  Energy is needed to make things happen
• Hertz


  The unit of frequency (Hz)
• Incident wave


  The wave coming from a source of light
• Infrasound


  Sound below a frequency of 20 Hz
• Inner ear


  The semi-circular canals that help you to balance, and your cochlea
• Kilohertz


  1 kilohertz (kHz) = 1000 hertz (Hz)
• Longitudinal


  A wave where the vibrations are in the same direction as the direction the wave moves
• Loudness


  How loud you perceive a sound of a certain intensity to be
• Medium


  The material that affects light or sound by slowing it down or transferring the wave
• Microphone


  A device for converting sound into an electrical signal
• Middle ear


  The ossicles (small bones) that transfer vibrations from the outer ear to the inner ear
• Oscillation


  Something that moves backwards and forwards
• Oscilloscope


  A device that enables you to see electrical signals, like those made by a microphone
• Ossicles


  The small bones of the middle ear (hammer, anvil, and stirrup) that transfer vibrations from the eardrum to the oval window
• Outer ear


  The pinna, auditory canal, and eardrum
• Oval window


  The membrane that connects the ossicles to the cochlea
• Pinna


  The outside part of the ear that we can see
• Pitch


  A property of sound determined by its frequency
• Rarefaction


  The part of a longitudinal wave where the air particles are spread out
• Receiver


  The device that absorbs the sound waves
• Reflected wave


  The wave that is reflected from a surface
• Reflection


  The change in direction of a ray or wave after it hits a surface and bounces off
• Reverberation


  The persistence of a sound for a longer period than normal
• Sound


  A series of compressions and rarefactions that move through a medium
• Speed of light


  The distance light travels in one second (300 million m/s)
• Speed of sound


  The distance sound travels in one second (330 m/s)