K-12 Science, CCSD, 2006 Light Photos, sounds, and clipart were inserted from Microsoft’s Office products unless noted.

K-12 Science, CCSD, 2006 Waves Remember? A wave is energy being moved from one place to another.

K-12 Science, CCSD, 2006 Light Waves Light is another kind of energy that moves in waves. Write down 6 words to describe light.

K-12 Science, CCSD, 2006 Light Waves Light is another kind of energy that moves in waves. Light waves do not need a medium. They can travel through nothing!

K-12 Science, CCSD, 2006 Light Waves Explain why we get light from the sun but not any sounds.

K-12 Science, CCSD, 2006 Light Waves Light waves can be reflected. Light waves can be refracted (bent). Light waves can be absorbed.

K-12 Science, CCSD, 2006 Light Wavelength Just like sound, light has different wavelengths. Review the parts of a wave:

K-12 Science, CCSD, 2006 Parts of a Wave A = Crest B = Trough D = one full wave = one wavelength = one period C = Amplitude C A B D

K-12 Science, CCSD, 2006 Light Wavelengths Light has different wavelengths. Red light has a large wavelength. Blue light has a shorter wavelength.

K-12 Science, CCSD, 2006 Light Wavelengths Red light has a large wavelength. Blue light has a shorter wavelength. Would it take longer for a red light wave or a blue light wave to go past a point?

K-12 Science, CCSD, 2006 Frequency Red light has a large wavelength. Blue light has a shorter wavelength. The shorter, blue wavelengths would go past quicker.

K-12 Science, CCSD, 2006 Frequency Large wavelength = low frequency Medium wavelength = medium frequency Small wavelength = high frequency

K-12 Science, CCSD, 2006 Frequency Don’t confuse the frequency with the speed of a wave. Here’s an analogy:

K-12 Science, CCSD, 2006 Frequency If you were looking down on a freeway... And all of the vehicles were going exactly 60 miles per hour (the same speed)...

K-12 Science, CCSD, 2006 Frequency Small cars going 60 miles per hour

K-12 Science, CCSD, 2006 Frequency Bigger cars going 60 miles per hour

K-12 Science, CCSD, 2006 Frequency Really big vehicles going 60 miles per hour

K-12 Science, CCSD, 2006 Frequency Speed = 60 miles per hour Small cars = high frequency (6) Bus = low frequency (1)

K-12 Science, CCSD, 2006 Frequency Light speed = 186,000 miles per second Blue light waves = higher frequency Red light waves = lower frequency

K-12 Science, CCSD, 2006 Frequency – Visible Light Red light Orange light Yellow light Green light Blue light Violet light

K-12 Science, CCSD, 2006 Frequency – Visible Light Red light Orange light Yellow light Green light Blue light Violet light

K-12 Science, CCSD, 2006 Frequency – Visible Light The light we use to see has all of these wavelengths in it.

K-12 Science, CCSD, 2006 So... How Do We See Colors? Let’s start with our eyes. To Brain Light waves

K-12 Science, CCSD, 2006 So... How Do We See Colors? If there is no light... To Brain Light waves

K-12 Science, CCSD, 2006 So... How Do We See Colors? If there is no light... To Brain

K-12 Science, CCSD, 2006 So... How Do We See Colors? If there is no light... To Brain you cannot see because there are no light waves reflecting to your eye. Our eyes only see light reflected off things!

K-12 Science, CCSD, 2006 So... How Do We See Colors? The green part absorbs all of the colors except green. It reflects green light. To Brain The red part absorbs all of the colors except red. It reflects red light.

K-12 Science, CCSD, 2006 EMR The light we see is part of a spectrum. Radio Microwave UltravioletVisibleInfraredX-rayGamma Ray E lectromagnetic R adiation S pectrum