8 Electromagnetic Waves Ultraviolet – can cause skin damage/cancer; helps body make vitamin D; used to kill bacteriaX-Rays – used in medical imagingGamma Rays – used in radiation therapies for cancer
9 LightObjects can absorb light, reflect light, or let light pass through them.Opaque – no light goes through, all is absorbedTranslucent – some light passes throughTransparent – almost all light passes through
10 LightPrisms work by refracting light and separating white light into the “rainbow” of colors (frequencies).Mirages occur when you have light passing through air of different densities (temperature).
11 LightWhen humans see color, they see the only that frequency of light being reflected back to their eyes, the rest of the color frequencies are absorbed.
12 Light White light is the combination of all colors. Humans see white when all light frequencies are reflected back.Black is all the frequencies of light being absorbed and none reflected.
13 Light Primary colors of light are red, green, and blue. Mixing these three colors of light produces white light.
14 LightPigments are colored material that absorbs some colors and reflects others.Primary pigments are magenta, cyan, and yellow.Mixing all the primary pigments produces black.
15 LightLasers are formed from coherent light – light of only one wavelength that travels with its crests and troughs aligned.Polarized light is also traveling in one direction.Polarized filters (used in some sunglasses) reduce glare by eliminating all but one direction of light.
16 LightOptical fibers rely on total internal reflection – when light travels from one medium to another is actually completely reflected at the boundary between the mediums.Used in communication wires, medical equipment, etc.Can transmit large amounts of data in a small fiber.