1. Lecture 33 Review for Exam 4 Interference, Diffraction Reflection, Refraction

2. An interference pattern from 2 slits is observed on a screen. If d is doubled 1.The interference pattern does not change 2.The fringe spacing doubles 3.The fringe spacing is halved 4.Need to know wavelength

3. Diffraction grating problem In order to determine the spacing d, of a diffraction grating (often called the grating constant), I shown a HeNe laser (λ=633nm) through the grating. On a screen 50cm away, I measured the distance between the central, m=0 bright fringe and the m=1 bright fringe and found the distance to be 9.65 cm. What is the d?

4. What is n for this material? Light incident from air, λ = 540 nm What is the critical angle for total internal reflection? 40 0 30 0

5. The interference pattern from 2 slits is observed. As λ is increased 1.The fringe spacing increases 2.The fringe spacing decreases 3.Does not change 4.Need to know λ 5.Need more information

6. Question What is the difference between diffuse and specular reflection? What is θ OUT ? 35 0 θ OUT AIR n=1.63 AIR

7. Using a 600 lines per mm grating At what angle will I find the m = 2 line for a wavelength λ = 530 nm?