1. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter 25: Interference and Diffraction

2. Figure 25.01 Coherent and Incoherent Wave Sources A coherent source produces waves that are in phase with each other (e.g., Lasers)

3. Figure 25.02 Constructive Interference of two Coherent Waves

4. Figure 25.03 Destructive Interference of two Coherent Waves

5. Figure 25.04 Phase Difference Due to Different Paths Constructive interference if: Destructive interference if:

6. Figure 25.05 Example 25.1 (Page 913)

7. Figure 25.06 How a CD is Read?

8. Figure 25.09 Thin Films and Phase Shifts due to Reflection An electromagnetic wave undergoes a phase change of 180° upon reflection from a medium of higher index of refraction than the one in which it was traveling. There is no phase change when the wave is reflected from a boundary leading to a medium of lower index of refraction.

9. Figure 25.10 Waves and Phase Shifts

10. Figure 25.11 Phase Shifts

11. Figure 25.14 Thin Films of Air

12. Figure 25.17 Young’s Double-Slit Experiment

13. Figure 25.18 Double-Slit Interference Patterns (using red light)

14. Figure 25.19 Double-Slit Maxima and Minima m is often called the order of the maximum

15. Figure 25.22Gratings Large number of slits per a small unit length Slits per cm = 1/cm per slit = 1/d Could be 50,000 slits per cm or 1/50,000 = 200 nm A Grating produces Very Narrow Maxima: A grating separates light with a mixture of wavelengths into its constituent wavelengths. See Example 25.6 on page 927.

16. Figure 25.27 Diffraction and Huygens’s Principle

17. Figure 25.31 Diffraction by a Single Slit

18. Figure 25.32 Single Slit Diffraction Minima The equation doesn’t have m =0 <= Nota bene

19. Figure 25.40 X-Ray Diffraction

20. Figure 25.41 X-ray Diffraction Maxima: Bragg’s Law

21. Homework Assignment 25.1, 25.4, 25.5, 25.6, 25.8 Please explain your answers Try the conceptual and multiple answer questions

22. End of Chapter 25