By: Kyle Wittkowski

  Sound is used to communicate  Without any sound, the world would be quiet  People make sounds to communicate by speaking from their vocal chords  People speak in different tones and pitches based on their emotion (ex. A girl screaming at a boy because he took her toy; this shows high pitch)  Other animals such as dolphins and whales also use sound to communicate and use echolocation to find prey How sound is used to communicate

  Terms to know:  Pitch - The perception of the frequency of a sound and it describes how high or low the sound seems (Pitch depends on the frequency; the higher the frequency of a wave, the higher the pitch, and the lower the frequency of a wave, the lower the pitch)  Frequency- The number of vibrations that occur per second  Intensity- The amount of energy per second carried through a unit by a wave (Sound waves of a higher amplitude (the height), have a greater intensity)  Loudness- Perception of the intensity of a sound wave (the greater the intensity (the energy), the louder the sound) Definitions

  This instrument is called a guitar and there are a variety of different types, but I am only going to be describing a homemade version of the acoustic guitar  It is a string instrument, therefore its sounds are formed from the different strings  The sound is formed by simply plucking the strings  This instrument does not need electricity, unlike the electric guitar The acoustic guitar

  The tightness of the string determines the pitch of the sound because it changes how frequent the strings vibrate  When the string is tighter, it creates more tension making the string vibrate quicker, creating a higher pitch.  When the string is looser, it creates less tension making the string vibrate slower, creating a lower pitch  When determining the pitch of the strings sound, you must look for the frequency of the waves (how frequent it vibrates) and see if the wave vibrates fast (high) or slow (low) How its pitch works

  When you pluck the string softly, the intensity of it is low; therefore, it sounds soft  When you pluck the string more powerfully, the intensity is a lot more high, so the sound is a lot louder  When determining the loudness of the instruments sound, you must look for the amplitude (the height of the wave) and see if the wave is short (soft) or tall (loud)  How hard you pluck the string determines the volume because it shows how much energy you’re putting into the string How its Volume/Amplitude works

  This is the original sound wave Original wave

 Sound with higher pitch - This is the original sound wave from instrument - This is the higher pitch sound wave from instrument - The waves frequency is faster making the pitch higher

 Sound with lower pitch - This is the original sound wave from instrument - This is the lower pitch sound wave from instrument - The waves frequency is slower making the pitch lower

 Sound with a louder volume This is the original sound wave from instrument -This is the louder volume sound wave from instrument -The waves amplitude is tall making the volume louder

 Sound with a lower volume - This is the original sound wave from instrument -This is the softer volume sound wave from instrument -The waves amplitude is very short making the volume very soft

  ed.org/EducationResources/HighSchool/Sound/fre quencypitch.htm ed.org/EducationResources/HighSchool/Sound/fre quencypitch.htm  I also used the notes for the definitions Cited Sources