2. Wave Shapes
• Wave front – shape of a wave is determined
by the shape of wave fronts
1. Plane wave – crests are in straight lines
2. Circular wave – crests are in circles
3. Wave Interactions
• Waves lose energy due to friction or when
they change mediums
• As a wave travels, it approaches boundaries of
different mediums
4. Types of Wave Interactions
1. Absorption - when a wave’s energy dies out
in a soft medium
– Damping – Amplitude of the wave decreases
over time
– Ex: Yelling into a pillow – the soft pillow absorbs
the sound
5. 2. Reflection - when a wave hits a hard
boundary and bounces off
– Ex: an echo – when you yell, the waves bounce
off a wall in the distance and travel back to you
6. 3. Diffraction - a wave drags around a corner,
causes part of the wave to turn & change
wave front
– Ex: talking to someone around a corner
7. • Also happens when plane waves go through a
small opening
– Ex: being able to hear someone through a door
that is cracked open
8. 4. Refraction - when a wave bends as it enters a
new medium
• it speeds up or slows down depending on
the medium
– Ex: Try catching a fish by reaching for what you
see.
9. 5. Scattering – change in direction of particles
because of collision with other particles
10. Why is the sky blue?
• Shortest l colors (BIV) get trapped and scattered by
gases in upper atmosphere (atm)
11.
12. Sunsets/Sunrises
• Light rays have a longer path to travel in atm
– Shortest l reflected off upper atm (GBIV)
– Longest l scattered in atm (ROY)
