Air law

SOUND 

- The sound is produced by the vibration (movement) of a body
- That vibration creates sound waves that travel in the air until they reach our ears.
- The sound waves get to our eardrum (tímpano) that sends electric signals to our brain (cerebro) and we can hear the sound 

The different ways of joining the sound qualities creates different kinds of music. The four qualities (pitch, duration, intensity and timbre) produce the main music elements (melody, rhythm, dynamic an timbric) 

The four sound qualities:
1. PITCH, is the sound quality that distinguishes high sounds (sonidos 

agudos) from the low sounds (sonidos graves). 

The pitch of sounds depends on the wave frequency: the vibration speed. It is measured in units called Hertzes (Hz) which show the number of vibrations per second. Infrasounds- 16 Hzs-20.000 Hzs- Ultrasounds. 

2. DURATION, is the sound quality that distinguishes long sounds (sonidos largos) from short sounds (sonidos cortos). It depends on the wave persistance: how long the wave lasts until fading out. 

3. INTENSITY, is the sound quality that distinguishes loud sounds (sonidos fuertes) from soft sounds (sonidos suaves). It depends on the wave amplitude: the distance between the points of highest vibration and repose of the object. It is measured in units called decibels (dB)