Sound

• two factors that determines the speed of a wave:

  -Elasticity of the medium.

  -Density of the medium.
• Sound is propagated by vibrations and therefore needs a medium to propagate the sound.
• The core of a loudspeaker vibrates (moves in an out)causing the surrounding air molecule

  s to be compressed and then stretched apart.

  A) Direction od movement⟶

  B) Rarefaction

  C) Compressions

  
• Reflection


  -also known as an echo

  -Is softer than the original sound(some of the energy is absorbed by the reflecting surface)