1. Light Optics

2. Sunglasses
What are they used for?
How do you think they work?

3. Light Interactions
Light can be reflected, transmitted, or absorbed when it strikes an object
The type of object effects what the light that passes through…

4. 3 Markers One wrapped in a box One wrapped in wax paper
One in a plastic bag
… What is the difference?

5. Transparent This material allows light to pass directly through
The light is not scattered
Examples:
Glass
A plastic bag
Air
Water

6. Translucent This material scatters the light that it goes through
Examples
Frosted glass
Wax paper

7. Opaque
This material reflects or absorbs all of the light that strikes it
Light cannot pass through
Example
Tightly woven fabric
Wood
Metal

8. Colors The color of opaque objects = the color of light it reflects
Your clothing
Black in color = all colors of light have been absorbed
White in color= all colors of light have been reflected
The color of translucent and transparent objects = the color of light it transmits
Instagram filters
Glass

9. Mix it Up
Combining colors results in a new color, but there is a difference between combining light and combining pigments
Light Pigment

10. Speed of Light
Fastest in a vacuum
Slowest in a solid

11. Reflection Light reflects in straight lines called rays
Two ways that light can be reflected
Regular Reflection
Light hits a smooth surface
Diffused Reflection
Light hits a bumpy uneven surface
Why is light reflected different on a metal can in comparison to a paper cup?

12. Mirrors
Plane: flat sheet that reflects an image that is the same size as the object
Light is direct and straight
Concave: curves inward like a bowl and reflects light rays so they meet at a focal point
Forms a virtual image (not real)
Convex: curves outward and reflects light so the rays do not meet and the object is smaller

14. Refraction
When light rays enter a medium, the light changes in speed, which causes it to bend, or change direction
Mirages: seeing puddles in the distance
Rainbows

15. Reading Read page 620- 622 and 626 – 627
Create a chart or using complete sentences describe the difference and similarities between concave mirrors, convex mirrors, concave lenses, and convex lenses.

16. Quick Check
What happens to light when it passes through the following objects? Is it absorbed, transmitted, or reflected?
Why do green apples and green traffic lights appear to be green?
If an actor’s pants are blue and shirt is green, what color is the light on the stage?
A tissue
A rag
A mirror
The window
The desk
There are 3 mirrors: in one you can see yourself, in another you are magnified, and in the third you look smaller. Which mirror is plane, concave, and convex?
Classify each of the items above as translucent, opaque, or transparent?

17. Electromagnetic Spectrum
The complete range of electromagnetic waves in order of increasing frequency.
Types
Radio
Microwaves
Infrared
Visible Light
The speed of each is constant, but their frequencies and wavelengths change.
Ultraviolet
Xrays
Gamma
Remember wavelength*frequency= wave speed

19. Radio waves Longest wavelength EM waves Uses: TV broadcasting
AM and FM broadcast radio
Avalanche beacons
Heart rate monitors
Cell phone communication
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

20. Microwaves Wavelengths from 1 mm- 1 m Uses: Microwave ovens
Bluetooth headsets
Broadband Wireless Internet
Radar
GPS
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

21. Infrared Radiation Wavelengths in between microwaves and visible light
Uses:
Night vision goggles
Remote controls
Heat-seeking missiles
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

22. Visible light
Only type of EM wave able to be detected by the human eye
Red, Orange, Yellow, Green, Blue, Indigo, Violet
Violet is the highest frequency light
Red light is the lowest frequency light
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

23. Ultraviolet Shorter wavelengths than visible light Uses: Black lights
Sterilizing medical equipment
Water disinfection
Security images on money
There is one more UV slide…

24. X-rays Tiny wavelength, high energy waves Uses: Medical imaging
Airport security
Inspecting industrial welds
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

25. Gamma Rays Smallest wavelengths, highest energy EM waves Uses
Food irradiation
Cancer treatment
Treating wood flooring
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram