1. Standard: Describe how the behavior of light waves is manipulated causing reflection, refraction, diffraction and absorption.
What am I learning today?
How do light waves change when they hit different materials?

2. Wave Properties of Light

3. What happens when Light waves hit a surface?

4. Reflection occurs when a wave strikes an object and bounces off
occurs with all types of waves
obeys the Law of Reflection – the angle of incidence is equal to the angle of reflection

5. Law of Reflection

6. Refraction
When a wave enters a new medium at an angle, one side of the wave changes speed before the other side, causing the wave to bend.

7. Refraction (cont.)
amount of bending depends on the speed of light in both materials
the greater the difference between the speeds of light in the two media, the more the light is bent
if light slows down as it passes into the new medium, the light is bent towards the normal (an imaginary line drawn perpendicularly through the surface of the material)
if light speeds up as it passes into the new medium, the light is bent away from the normal

8. Refraction (cont.)
amount of refraction depends on the wavelength of the light
red light is bent the least
violet light is bent the most
white light can be separated into colors by refraction in a prism

9. Diffraction bending of light around a barrier or through an opening
occurs with all types of waves

10. Diffraction Website

11. Interference caused when light waves overlap each other
constructive – interact to build up wave
destructive – interact to reduce wave
occurs in all types of waves
white light can be separated into colors by diffraction and interference using a diffraction grating

12. Polarization Ordinary light has waves that vibrate in all directions
A polarizing filters acts as though it has tiny slits in one direction
Only some of the light (vibrating in the same way of the “slit”) can pass through a polarized filter
Best example of a polarized filter is sunglasses
Polarization Website

13. Reflection Example
Complete the figure to the right to show the Law of Reflection.

14. Refraction Example
Complete the path of a light ray as it goes through water, glass, and back into air

15. A prism is an example of Refraction

16. Prisms - ROYGBIV
Label the colors of the spectrum you observed. What caused the white light to separate into colors?

17. Copy the organizer at the bottom of your notes sheet
Copy the organizer at the bottom of your notes sheet. Match the Description to the behavior.
Behavior
(diffraction, reflection, absorption, refraction)
Description of Wave Motion 1.
Bounces off the surface at the same angle it hit with 2.
Travels through material, but at an altered bent angle 3.
Travels through the material until it encounters an obstacle or hole, which it bends around 4.
Cannot travel all the way through the material