1. DO NOW
In your notes… answer the following question using bullet points:
What do you know about light?
Causes sunburn
Allows plants to make food
Allows us to see
Form of energy

2. Properties of Light

3. Essential Question
“How do astronomers learn/study what is beyond our atmosphere?”
Today’s Objectives:
Investigate the properties of light
Explain the role of light in astronomy

4. Light is the common term for electromagnetic radiation traveling through space as waves.
Speed of light = 3.0x108 m/s

5. Electromagnetic Radiation
Electromagnetic Radiation is any form of energy that moves like a wave through space
Organized on the Electromagnetic Spectrum according to wavelength and frequency

6. Parts of a wave Wavelength (l) = Length of one wave
Measured in unit of distance (m, nm, etc.) l
Frequency(v) = number of cycles in one second
Measured in hertz 1 hz = 1 cycle/second

7. Electromagnetic Radiation
There are many
Different l and n
Higher Energy = Higher Frequency / Lower Wavelength
Radio waves, microwaves, x rays and gamma rays are all examples.
Visible Light is only the part our eyes can detect. a m m a R a d i o R a y s w a v e s

8. Electromagnetic Spectrum

10. Creation of light Light can be created in 3 ways: The Sun
Light Bulbs – Electricity or batteries
Chemicals – Fireworks, explosion, chemical reactions

11. Refraction
The bending of light as it passes between materials of different optical density

12. Reflection
The abrupt change in direction or bouncing off of a wave

13. Color Visible Light Spectrum (ROY G. BIV)
White light is a mixture of every color of the rainbow
Black is the absence of color
Observed color – the color you see is the color the object reflects back to your eyes