What is sound?*
 Sound begins with a vibration.
 Sounds travel in waves through a medium.
What is a wave?*
A disturbance and vibration
through a medium
What is a wave?*
Energy is transferred
through a wave.
What is a wave?*
 Energy is transferred through a wave.
 Two types of waves
1. Mechanical waves- travel through a medium (matter)
2. Electromagnetic waves- do not need a medium
(matter) to travel
 Examples?
1. Mechanical waves- travel
through a medium (matter)
Mechanical Waves*
1.





Longitudinal Waves
The motion of the medium is parallel to the motion
of the wave
Also known as P-waves
Back and Forth Waves
Push and Pull
**Sound Waves**
Mechanical Waves*
Transverse Waves
 The motion of the medium is perpendicular to the
motion of the wave
 Also known as S-waves
 Up and Down Waves
1.
Longitudinal Waves*
Compression
 When waves are close
together
Rarefaction
 When waves are far apart
Transverse Waves*
Crest- highest Trough-
point on a
wave
lowest point
on a wave
Transverse Waves*
 Amplitude- Volume of a
wave (height of a wave)
 As wave height increases,
volume increases
 Measured in Decibels
(dB)
 Frequency- Pitch, high or
low (length of a wave), the
number of waves there are
 More waves = high
frequency
 Less waves = low
frequency
 Measured in Hertz (Hz)
Wavelength
 Distance between two of the same type of points of a
wave
 Crest to Crest
 Trough to Trough
 Compression to Compression
 Rarefaction to Rarefaction
Amplitude versus Frequency
Amplitude
 Which one will have the
higher volume?
Frequency
 Which one will have the
higher pitch?
Diagram of a Transverse Wave*
AMPLITUDE
TROUGH
CREST
MATTER
WAVELENGTH