LT 2.3 - Properties of Sound

What is a Sound Wave?

Longitudinal waves created when particles of the medium vibrate back and forth

Longitudinal Waves are…

Particles that vibrate back and forth, PARALLEL to the direction the wave travels

Transverse Waves are…

Particles that vibrate up and down, PERPENDICULAR to the direction the wave travels

Pitch

Determined by the waves frequency, it’s the sound meaning higher frequency= higher pitch

Volume

Determined by the waves amplitude meaning higher amplitude= louder sound

What is Interference

Happens when two waves overlap and interact with one another

Constructive Interference

Happens when waves are in phase, meaning they match up (high points overlap with high points, low points overlap with low points)

Amplitudes add together

Destructive Interference

Happens when Waves are out of phase, meaning they are opposite (high points overlap with low points) The wave amplitudes cancel out (subtract).

The Droppler Effect

When the source of a sound is moving, the movement changes. Either gets “stretched out” or “compressed. Changed the pitch that you hear