17.1 Mechanical Waves
What is a mechanical wave?
• A mechanical wave is a disturbance in
matter that carries energy from place to
place
What do mechanical waves
require?
• Mechanical waves require a
medium.
What is a medium?
• A medium is the material through which a wave
travels.
How are mechanical waves
created?
• Mechanical waves are created when a
source of energy causes a vibration to
travel through a medium.
What is a transverse wave?
• A transverse wave causes the medium to
vibrate @ right angles to the direction the
wave travels.
Draw a picture of a transverse
wave: label crest, trough, rest
Name an example of a transverse
wave.
• Shaking a rope & shaking a blanket are
examples of transverse waves.
What is a longitudinal wave?
• A longitudinal wave is a wave in which the
vibration of the medium is parallel to the
direction the wave travels.
Draw a longitudinal wave: label
compression and rarefaction
Name an example of a longitudinal
wave.
• Slinky springs & P waves (aka primary
waves) produced by earthquakes are
examples of longitudinal waves.
What is a surface wave?
• A surface wave is a wave that travels
along a surface separating 2 media – like
air and water
What is the most familiar kind of
surface wave?
• Ocean waves are the most familiar surface
waves.
A surface wave causes a bobber
floating on the water to move
an up-and-down motion, as
well as a back-and-forth
motion. The combined effect of
both types of wave motion
causes the bobber to move in a
circle
Bobber buoy…
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