1. Waves

2. Two Types Longitudinal Energy moves in the same direction of travel
Transverse
Energy moves perpendicular to the direction of travel

3. Parts of a Wave Crest Wavelength High point in a wave
Trough
Low point in a wave
Node
Points of no displacement
Amplitude
The height of the wave
Wavelength
the distance from one crest to the next crest
Frequency
The rate the crests pass a given point

4. Medium Matter (material) for waves to move through
Mechanical waves require a medium
Electromagnetic waves do not require a medium
Dense mediums allow waves to move more quickly

5. Propagation of Waves
Except for surface waves, waves propagate outward spherically in 3D - like the layers of an onion.
The layers of an onion, are a good representation of how waves look as they travel-
In every direction equally at the same time!

6. If the Wave propagated out on a separate 2D plane, I wouldn’t see it.
Wave hitting my eye – I can see it!
If waves propagated in only 2D like waves on a pond, then if we moved the candle up a little higher we wouldn’t be able to see it.

7. Longitudinal Wave
Examples
Sound waves
Seismic P waves

8. Transverse Waves
Examples
Light
Seismic S waves
Vibrations in strings

9. Sound Pitch How high or low the sound is Depends on Frequency Volume
How loud or quiet the sound is
Depends on Amplitude

10. Energy Frequency How is energy related to:
Amplitude?
They are directly proportional:
Increase Frequency = Increase Energy
Increase Amplitude = Increase Energy
Amplitude

11. Interference- when waves interact with each other
Reflection
A change in direction of waves when they bounce off a barrier
Refraction
A change in the direction of waves as they pass from one medium to another
Diffraction
a change in direction of waves as they pass through an opening or around a barrier in their path

12. Electromagnetic Waves

13. How do we know light travels in waves?
 "Is light a wave or a stream of particles?“
Light exhibits certain behaviors characteristic of waves:
Refraction, Diffraction and Reflection
Interference
Doppler Effect

14. Properties of Light
Light waves do not need a medium the same way sound does
Light is a wave of energy
Each wave is made up of a photon of light
A photon is a “bundle” of energy
This bundle of energy excites other charged particles because of its charged properties
This is why light makes things feel warm

15. Light Frequency = Type of light and color
Our eyes are sensitive to light energy.  We perceive a low frequency light as red or yellow and a high frequency as blue or violet.

16. White Light Makes Vision Possible
White Light is actually made up of ALL the different colors – each color is made up of its own frequency and wavelength.

17. Color
When we look at something, we see the color that is reflected. For example, something red looks red because it is absorbing all of the other colors and reflecting the red wavelength.
Reflected
Incident Beam

18. Color What color would something be if it reflects all wavelengths?
What color would something be if it absorbs all wavelengths?