1. 10/13 - 7th Grade Agenda Collect: HW: p.35- 36
Transparent, Translucent and Opaque Materials
Video: Light & Color
Class Reading: p
HW: Workbook: p

2. Electromagnetic Wave
An electromagnetic wave consists of vibrating electric and magnetic field that move through space at the speed of lig____ ht

3. What are some examples of electromagnetic waves?
Radio Waves
TV Signals
Microwaves
Infrared rays
Light
Ultraviolet rays
X-Ray

4. How fast do electromagnetic waves travel?
It is the fastest thing in the universe
300,000 km per second
186,000 miles per second
It takes 8 minutes for light to travel from the sun to the earth
It takes 3 million years for light to travel from the nearest galaxy (andromeda) to the earth

5. Electromagnetic Wavelength

6. How do we use Radio Waves?
Radio & TV signals
Microwave Oven
Radar
MRI
Cell phone

7. Using Microwaves
Why do you see sparks you put metal objects in a microwave?
Because of the build up of electrical energy in the metal
The long wave length of Microwaves can pass right through glass and plastic. That is why microwaves do not heat glass and plastic containers.

8. How do we use Infrared Rays?
Conventional Oven
Heat Lamps
Thermograms

9. Visible Light makes up only a small part of the electromagnetic spectrum

10. Transparent Materials
Transparent material trans_____ most of the light that strike it.
mit

11. Translucent Materials
A translucent material sca____ light as it passes through, just as smoke, fog, and clouds scatter light as it passes through the air.
tters

12. Opaque Materials
An opaque material refl_____ or absorbs all of the light that strikes it.
ects

13. Why does the apple appear red?
Because the red light reflect it.
All other light are absorbed.

14. What do you notice about the apple when it is shown in red light?

15. What do you notice about the apple when it is shown in green light?

16. What do you notice about the apple when it is shown in blue light?

17. What are the three primary colors of light?
Red, Blue, Green

18. What are the three primary colors of pigment?
Yellow, Magenta, Cyan
What color do you get when you combine the three primary colors of pigment?

19. Why do three primary colors of pigments produce black instead of white?
As pigments are added together, fewer colors of light are reflected and more are absorbed