1. 11.1 – Standing/ Stationary Waves
Topic 11 – Wave Phenomena
11.1 – Standing/ Stationary Waves

2. Standing Waves Formation of standing waves
Standing waves are formed when two identical waves met each other travel in opposite directions.
Wiki – Waves on a string

3. Standing Waves
The result of this is a wave where the peaks simply move up and down but DO NOT PROGRESS.

4. Standing vs Progressive Waves
Amplitude
All points on the wave have different amplitudes. The maximum being 2A (at the antinodes) and 0 (at the nodes)
All points on the wave, have the same amplitude
Frequency
Oscillate with the same frequency
Wavelength
Twice the distance for one node to the next node
Shortest distance between two points that are in phase
Phase
All points between one node and the next node are in phase
All points along a wavelength have different phases
Energy
Energy is not transmitted by the wave but it does have an energy associated with it.
Energy is transmitted by the wave.

5. Formation of Standing Waves

6. Formation of Waves in Closed Pipes

7. Formation of waves in open pipes

8. 11.2 Doppler Effect
The change in pitch of a sound wave due to a change in frequency of the wave is called the Doppler Effect.
It is caused by the relative motion of the SOURCE and the DETECTOR

9. Moving Source

10. Moving Observer

11. Doppler Effect and EM radiation
The EM spectrum travels at c through a vacuum but if the velocity of the observed EM radiation in a lot smaller than c then we can use the following equation to calculate the change in frequency
For v << c

12. Doppler Effect Equations

13. Using the Doppler Effect!
– Outline an example in which the Doppler Effect is used to measure speed.

14. 11.3 Diffraction More in depth look at diffraction Huygens’ Principle

15. Diffraction from a single slit
What is the diffraction pattern shown on a screen when a wave is diffracted around a single slit?

16. Explaining the diffraction pattern

17. Explaining the diffraction pattern

18. Explaining the diffraction pattern

19. Explaining the diffraction pattern

20. Explaining the diffraction pattern

23. 11.4 Resolution
If two sources sources of light are very close in angle to each other they can sometimes be seen as one light source.
If we can detect that there are two light sources then we say the light sources are resolved
The ability to do this depends on the RAYLEIGH CRITERION

24. Rayleigh Criterion

25. Rayleigh Criterion
If the sources are to be just resolved, then the minimum of one diffraction pattern is located on top of the maximum of the other diffraction pattern.
For a SLIT – the minima was located at
For a CIRCULAR APERTURE -

26. Importance of Resolution
Research the importance of resolution in the development of the following technologies
CDs
DVDs
Electron Microscope
Radio Telescopes

27. 11.5 Polarisation