1. Light

2. Light is a wave! The Nature of Light What is Light? Light can
1. travel in straight lines
2. reflect
3. refract
4. transmit energy
Light is a wave!

3. LIGHT WAVES Electromagnetic Waves—Do not need a medium Transverse wave
Oscillating electric and magnetic fields

4. c = λf Speed of Light All EM waves travel at the speed of light (c)
c = 3.00 X 108 m/s (in a vacuum)
Wave speed equation is still valid:
c = λf
What happens to the wavelength if frequency is increased?

5. Decreasing Wavelength 
Increasing Frequency 

6. Frequency, Wavelength, & Energy
As the frequency of a light wave increases, so does its energy.
Gamma rays are dangerous to us because they have high energy and a short wavelength (smaller than our cells!)
Radio waves are harmless to us because they have low energy and long wavelengths

9. Concept Check
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10. Visible Light Spectrum:
Visible light is the portion of the
electromagnetic spectrum which stimulates the retina of the
human eye.
Visible spectrum
wavelengths range
from about 400 nm (violet) to 760 nm (red).
Visible Light Spectrum:
ROYGBV

11. Intensity of Light The inverse square law
The brightness of the light decreases by the square of the distance .
Like sound waves light spreads 3-D

12. POLARIZATION
Manipulating a wave so that it only oscillates in only one plane of direction.

13. POLARIZATION Two ways to Polarize Light: Reflection
Polarizer- blocks out all but one direction that light can travel

14. Concept Check
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15. POLARIZATION What is happening to the light? Explanation
Fun with polarized light

16. Concept Check
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