What is Sound?
![Picture](/uploads/1/8/7/8/18780660/9827357.png?394)
- Sound is a disturbance that travels through a medium as a longitudinal wave.
- All sound waves start with a vibration.
- Particles move the medium along. There are two ways to describe the particles. One is rarefaction and one is compression.
- Compression means the particles are close. Rarefaction means the particles are far apart.
Types of Waves
![Picture](/uploads/1/8/7/8/18780660/3178984.png?399)
An illustration of the definitions of compression and rarefaction
- This illustration also shows longitudinal and transverse waves.
- The other type of wave (not shown) is called a surface wave. A surface wave is a combination of a transverse wave and longitudinal wave.
How sound waves are made
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- Vibration takes a big part of sound.
- Sound waves are made when the vibration of an object occurs.
- The vibrating air then causes the human eardrum to vibrate, which the brain interprets as sound.