Mr. Jackson 5-3-12 Light is an EM wave (not requiring a medium) EM waves are produced by radiation which is the transfer of energy in the form of a wave The Speed of Sound was 343m/sec The speed of light is 300,000,000m/sec This is 880,000 times faster than the speed of sound If you could run at the speed of light you could circumnavigate the earth 7.5 times per second It takes 8.3 min for the sun to transmit light to the earth The entire range of EM waves is called the EM spectrum Longest Wavelength (over 30 cm) FM and AM radio and analog television signals are broadcast using Radio waves Wavelength between 1mm and 30 cm Microwave ovens, Cell Phones and Radar( Used to detect speed of a car) use microwaves. Used to detect heat Military and Fire Kitchens to keep food Hot IR thermometer The only part of the EM Spectrum you can see. The colors are Red, Orange, Yellow, Green, Blue, Indigo, Violet Roy G. Biv More violet than violet (Ultra Purple) Commonly known as UV Tanning beds, black light, ect. UV CAUSES CANCER!!! UV Causes sunburn UV does allow the body to utilize vitamin D Will pass through many materials Used in medical diagnostics Used for security devices in airports ect. Have the shortest wavelength Penetrate most materials easily Used for radiation treatment for cancer Also used to kill harmful bacteria in food Light waves can be reflected by using a mirror The law of reflection states that the angle of incidence is equal to the angle of reflection Incidence is the arrival of a beam of light at a surface Objects that produce visible light are called luminous Objects that are visible but do not produce light are called illuminated When light becomes dimmer while traveling through a medium such as air is Absorption Scattering is where light becomes dimmer due to the particles of light spreading out Refraction of light is the bending of light This process occurs because light travels slower through solids and liquids than it does air Refraction will separate visible light into the 7 primary colors by using a prism A Transparent object allows light to be transmitted through the object (Glass) A Translucent object transmits light but not an image ( Wax Paper) An opaque object will not transmit light or an image Red, Blue and Green are the Primary colors of light. When the colors of light combine they undergo color addition which produce the secondary colors of light which are Magenta, Cyan, and Yellow Television screens produce the colors Red, Blue and Green. New Televisions with 3-D Technology and LED Technology use Yellow in the pixels to produce more vibrant color schemes When all the Primary colors mix they produce White light The primary pigments are Yellow, Magenta, and Cyan and by the process of color subtraction they produce the Primary Colors of light When they all mix together they produce Black A plane mirror has a flat surface. Images appear the same size but are reversed right to left Concave Mirror makes objects appear smaller shaped like the inside of a spoon Convex Mirror Makes objects appear larger shaped like the back of a spoon A lens is a transparent object that refracts light Convex Lenses is thick in the middle and narrow on the edge. Used in magnifying lenses and in cameras Concave Lenses are thin in the middle and thick on the edges. Used in eyeglasses and microscopes Nearsightedness is a condition where they eye is too long. These people see things up close but not far away Farsightedness is there the eye is too short. These people can see far away but not up close Color Blindness where the cones that receive color do not function properly Lasik is a surgical procedure where laser is used to reshape the lens of the eye. It is minimally invasive although the cornea is cut. PRK is a surgical procedure that is used to reshape the lens. In this procedure the cornea is burned away by a laser and the recovery is longer however the correction tends to last longer Produces intense light of only 1 wavelength and color. The waves in a laser behave as 1 wave Thin glass tubes that transmit light. Used for data and voice communication also used for video Light in a pipe Polarized light is light that has passed through a filter and only 1 plane of the light is allowed to pass.