1. Review Waves

2. Wave Pulse = short burst of Energy

3. 2 Types of Traveling Waves
Longitudinal Waves
Medium moves Parallel to the direction energy travels
(sound)
Transverse Waves
SHOW Family Tree structure: see next hidden slide
Medium moves Perpendicular to the direction energy travels

4. Slinky Demo – Transmitting a wave “Pulse”
1) Pulse Travels (energy) 2) Pulse Refection (2 types) 3) Vary f 4) Standing Waves 5) 2 Wave types

5. Wave “Phase” and “Phase Difference”
Each wave cycle has 360o
Each point on the wave is a phase of the wave
Points on the wave 360o apart are said to be in “phase” (or 720o,1080o, etc.)
Points on the wave 180o apart are said to be exactly out of “phase” (or 540o,900o, etc.)
Here, show via 2 Spring example when two masses are exactly IN & OUT of phase

6. Displacement vs Position Graphs
Copy this graph as it’s sketched on the chalkboard
Crest = top of wave Trough = bottom of wave
Wavelength = distance of one complete wave cycle
Amplitude = energy of a mechanical wave (ex. Loudness for sound)
D [m]
Corresponding to the ripple tank... +
Wavelength []
crest
crest
amplitude
x [m]
trough
trough
Line of Equilibrium -

7. 2 Types of Interference:
Constructive: waves add up to become stronger
Destructive: waves add up to become weaker

8. Thick lines = Crests
Thin lines = Troughs
Thus: Red dots = constructive interference (2 crests or 2 troughs)
And: Blue dots = destructive interference (Meeting of a crest & trough)

12. Resonance All objects will oscillate (vibrate)at
their own natural frequency

13. Standing Waves: DRAW & LABEL
On a standing wave, wave “appears” to be fixed in space, changing in amplitude only
Antinode = spot of total
constructive interference (max. amplitude)
Black Line = Resultant Standing Wave
Node = spot of total
destructive interference (no amplitude)

14. Light = EM (Electromagnetic Wave)
Not all light is visible

15. Speed of light

16. UG: Describe the Nature of Reflection
The Reflection of Light
Demo
= the "Normal"
Angle measured from the Normal
Incident angle,
= Reflected angle
Law of
Reflection
SUNY

19. Diffraction = Waves Spreading Circularly behind barrier
Mechanical & EM Waves both Diffract

20. Incident Ray
Reflected Ray
Refracted Ray

21. If light enters a more dense medium
Bends closer to the normal!

22. Light entering a less dense medium
It bends away from normal

23. n1 sinθ1 = n2 sinθ2