1. LIGHT

2. LIGHT HAS WAVE PROPERTIES. THE TYPE OF LIGHT IS CHARACTERIZED BY WAVELENGTH – THE DISTANCE FROM ONE PEAK TO THE NEXT. LIGHT ALSO HAS PARTICLE PROPERTIES.

3. A BEAM OF LIGHT CAN KNOCK ELECTRONS OFF A METAL SURFACE. THIS IS A DEMONSTRATION OF THE PARTICLE NATURE OF LIGHT AND IS CALLED THE PHOTOELECTRIC EFFECT.

4. VISIBLE LIGHT IS IN THE RANGE OF 400 TO 700 NANOMETERS, nm. A NANOMETER IS 10 -9 METERS – ONE BILLIONTH OF A METER.

6. ROY G BIV RED ORANGE YELLOW GREEN BLUE INDIGO VIOLET A GOOD WAY TO REMEMBER!

7. EXAMPLE OF STELLAR SPECTURM DARK LINES REPRESENT ELEMENTS IN OUTER ATMOSPHERE. DIFFERENT ELEMENTS EMIT OR ABSORB DIFFERNET WAVELENGTHS OF LIGHT. THIS PROPERTY CAN BE USED TO IDENTIFY WHAT ELEMENTS ARE PRESENT IN STARS.

8. OUR EYES AND MIND DO SOME INTERESTING THINGS WITH LIGHT AND OPTICS. 1)PRINTING IS DONE WITH A SERIES OF VERY SMALL DOTS OF ONLY 4 COLORS. WE DON’T SEE THE SMALL DOTS, BUT OBJECTS AND COLORS. 2)IF STILL IMAGES ARE SHOWN TO US FAST ENOUGH, WE SEE THEM AS MOTION. TELEVISION AND MOTION PICTURES USE 34 FRAMES PER SECOND.

9. COLORS FROM DOTS - PRINTERS PRINT IMAGES AS A SERIES OF DOTS USING ONLY 4 COLORS, CYAN, MAGENTA, YELLOW, AND BLACK. THE COLORS YOU SEE ARE COMBINATIONS OF DOTS OF THESE 4 COLORS.

10. CYAN MAGNETA YELLOW

11. THE DOPPLER EFFECT CAN ALSO CHANGE THE WAVELENGTH OF LIGHT. YOU SHOULD BE FAMILIAR WITH THE DOPPLER EFFECT AND SOUND. WHEN A CAR IS BLOWING ITS HORN AND SPEEDING TOWARDS YOU, THE CAR HORN WILL BE AT A HIGHER FREQUENCY (SHORTER WAVELENGTH) THAT WHEN IT IS MOVING AWAY FROM YOU (LOWER FREQUENCY AND LONGER WAVELENGTH). THE DOPPLER EFFECT IS USED IN ASTRONOMY TO DETERMINE HOW FAST STARS ARE MOVING TOWARDS US OR AWAY FROM US.

13. THE SPEED OF LIGHT IN A VACUUM IS A CONSTANT. 186,000 MILES PER SECOND OR 299,792,458 m/s NOTHING CAN GO FASTER. LIGHT DOES MOVE SLOWER IN OTHER MATERIALS.

14. Falcon can see a 10 cm. object from a distance of 1.5 km. Fly's Eye has a flicker fusion rate of 300/s. Humans have a flicker fusion rate of only 60/s in bright light and 24/s in dim light. Penguin has a flat cornea that allows for clear vision underwater. Penguins can also see into the ultraviolet range of the electromagnetic spectrum. With eyes mounted laterally on their heads, pigeons can view 340 degrees … everywhere except in back of their heads.