1. Electromagnetic Radiation and Light
Ms. Chapo
7th Grade Science
LaVilla School of the Arts

2. GOAL – page 12
I CAN recognize the order of the EM spectrum based on wave frequency and their common uses.

3. Lets recap stuff about EM waves…
They do NOT need a medium to travel
They only travel through transverse waves
The Sun is a major source of EM waves

4. What is radiation?
Radiation is the transfer of energy as EM waves.

5. What is in the EM spectrum?
There are 7 EM waves that are part of the spectrum:
RADIO WAVES
MICROWAVES
INFRARED LIGHT
VISIBLE LIGHT
ULTRAVIOLET LIGHT (UV)
X-RAYS
GAMMA RAYS

7. DRAW THIS!

8. Can you make your OWN pneumonic?V- U- X- G-

9. Types of EM radiation MAKE A 2 COLUMN CHART LIKE THIS:
TYPE OF EM RADIATION
USES
RADIOWAVES
MICROWAVES
INFRARED LIGHT
VISIBLE LIGHT
UV LIGHT
X-RAYS
GAMMA RAYS

11. Types of EM radiation ANSWER KEY: TYPE OF EM RADIATION USES RADIOWAVES
Radio and TV
MICROWAVES
Cooking, radar, TV, other
INFRARED LIGHT
HEAT from sun, fires, radiators
VISIBLE LIGHT
Things can be seen
UV LIGHT
Absorbed by skin, florescent tubes
X-RAYS
See inside of bodies
GAMMA RAYS
Medical treatment (kills cells)

12. What about the SUN?
The Sun gives off mostly visible light, but gives off radiation in ALL areas of the EM spectrum!

13. How much is too much radiation?
- The HIGHER the frequency, the MORE ENERGY that wave has = more dangerous.
Like UV rays and gamma rays
Gamma rays kill cancer cells
The LOWER is frequency, the LESS ENERGY that wave has = less dangerous.
like radio waves, microwave, infrared, visible light

14. NEW GOAL – page 14
I CAN identify the order of colors on the visible spectrum based on wave frequency and how colors are viewed.

15. VISIBLE LIGHT IS THE ONLY PART OF THE EM SPECTRUM HUMANS CAN SEE!

16. What are all of those colors again??
Red
Orange
Yellow
Green
Blue
Indigo
Violet

17. The longest wavelength = RED The shortest wavelength = VIOLET
What determines the color of light? FREQUENCY!
The longest wavelength = RED
The shortest wavelength = VIOLET

18. How do we see white or black?
When we see WHITE… ALL colors of ROYGBIV are reflected
When we see BLACK… ALL colors of ROYBGIV are absorbed

19. Exit ticket
Why do we see a tree frog as the color green?