1. Bell Work: Spring Break
When did you see a reflection?
When did you experience constructive interference?
When did you see light that had been refracted?
Other than visible light, what part of the electromagnetic spectrum did you encounter? In what context?

3. Electromagnetic Spectrum
Dual Nature
Can act like a particle (photon)
Can act like a wave

4. Electromagnetic Spectrum
Dual Nature

5. Electromagnetic Waves
Waves of oscillating electric and magnetic fields
Travel in a straight line unless

6. Electromagnetic Waves
they reflect,
they refract,
or they are diffracted.

7. Bell Work: Dual Nature Light can act like a _____ or a _____.
A particle of light is called a _____.
When talking about light, you are talking about all _____ parts of the EM spectrum.
Which part of the EM spectrum has the highest frequency?
Which part of the EM spectrum has the most energy?

8. Electromagnetic Particles
Created in small packets called photons.
Photons are released
from atoms when electrons give off energy (b).
Photons are absorbed
when they run into an electron (a).

9. Electromagnetic Particles
Travel at the speed of light unless
they are absorbed
when they run into an electron
Then they travel at the speed of light until it all happens again absorbed emitted
So, electromagnetic waves appear to move slower when they travel through matter.
and reemitted from the atom.

10. Electromagnetic Spectrum Practice Problem Answers:
242 m and 3.08 m
0.122 m
19,700 s
4.07 x 1016 m
3.80 x 10-7 m
3 x 1014 Hz
f = 5.4 x 1014 Hz
0.3 m
3.84 x 108 m
6.30 x m

11. Visible Light Spectrum Red Orange Yellow Green Blue Violet
RED GREEN BLUE
** primary light colors **
** 1/3 of white light **

12. ** secondary light colors **
RED GREEN BLUE
YELLOW CYAN
MAGENTA
** secondary light colors **
** 2/3 of white light **

13. ** absorb 1/3 of white light **
PIGMENTS
** primary pigments **
** absorb 1/3 of white light **
**reflect other colors – that’s what you see**

14. Cyan Absorbs Red MAGENTA Yellow Absorbs Absorbs Green Blue Blue
Green and
Red
Green
Absorbs
Blue and
Red
RED
Absorbs Blue & Green

15. * secondary light colors * * absorb 2/3’s of white light *
*reflect other color – that’s what you See*