NSF North Mississippi GK-81 The Electromagnetic Spectrum Different wavelengths of EM waves. These wavelengths of light and others make up a spectrum.

NSF North Mississippi GK-82 On the Spectrum… Left SideRight Side Type of Wave Wavelength Frequency Energy

NSF North Mississippi GK-83 VISIBLE LIGHT Electromagnetic waves we can see.

NSF North Mississippi GK-84 Visible Spectrum The visible spectrum contains seven colors. Each of these colors corresponds with a particular wavelength. –Longest wavelength= red light –Shortest wavelength= violet (purple) light

NSF North Mississippi GK-85 How can I remember the seven colors of the visible spectrum? ROY G BIVROY G BIVROY G BIVROY G BIV EDED RANGERANGE ELLOWELLOW REENREEN LUELUE NDIGONDIGO IOLETIOLET

NSF North Mississippi GK-86 White Light White light is not a single color; it is made up of a mixture of the seven colors of the rainbow.

NSF North Mississippi GK-87 Colour We can demonstrate this by splitting white light with a prism: This is how rainbows are formed: sunlight is “split up” by raindrops.

NSF North Mississippi GK-88 Why do we see color? When our eyes see different wavelengths of light in the visible spectrum, we see colors.

NSF North Mississippi GK-89 Seeing colour –What we actually see is the light an object reflects or in some cases the light an object produces. For example, a red book only reflects red light: White light Only red light is reflected How do humans see color?

NSF North Mississippi GK-810 Or… A red stoplight appears green because it produces red light. –It’s LUMINOUS!

NSF North Mississippi GK-811 Seeing colour –Absorption – the disappearance of an electromagnetic wave into a medium. It’s the opposite of reflection! White light Only red light is reflected The colors that don’t get reflected, are absorbed. It absorbs all the other colors. (OYGBIV)

NSF North Mississippi GK-812 Sun’s Rays (White Light) Green Wavelength of light Absorbs all other colors

NSF North Mississippi GK-813 A white hat would reflect all seven colors: A pair of purple pants would reflect purple light (and red and blue, as purple is made up of red and blue): Purple light White light

NSF North Mississippi GK-814 Using coloured light What about an outfit? White light Shorts look blue Shirt looks red

NSF North Mississippi GK-815 Black When you see black, all of the wavelengths of light are absorbed and no light is reflected back at you. White light Nothing is reflected. All visible light is absorbed.

NSF North Mississippi GK-816 Moving on to the HUMAN EYE You will now become blind. –You have 5 minutes to figure out how you are going to take halfway organized notes on the back of your Color Notes sheet. –Remember: these notes will be used on the test! They need to be legible!

NSF North Mississippi GK-817 TheHumanEye

NSF North Mississippi GK-818 HA! Even if you’re peeking, you can’t see anything!