Presentation on theme: "Wave Nature of Light. 1. What property of light determines the color? 2. T F The color white is the presence of all colors? 3. What are the 3 primary."— Presentation transcript:
Wave Nature of Light
1. What property of light determines the color? 2. T F The color white is the presence of all colors? 3. What are the 3 primary colors? 4. What are the 3 primary pigments? 5. What happens if I put 2 polarizing filters at 90 degrees to each other?
Last section we discussed the ray nature of light and how we came up with the speed of lightspeed 1665 Grimaldi showed that the shadows left by light are not perfectly sharp ◦ Explained this as the diffraction of light or the bending of light as it passes through openings Huygens finally gave support to diffraction of light by explaining the bending of light through openings 1666 Newton performed experiments on the color of light by passing a narrow strip of sunlight through a prism to separate colors of light
Was finally accepted that it is the wavelength of the light that causes it to diffract at different amounts ◦ Thus the visible light that we see is from wavelengths of 400nm (violet) to 700 nm (red)
There are 3 primary colors of light which are red, green, and blue. If we add any 2 primary color we get the secondary colors magenta, cyan, and yellow Primary colors are defined as any 2 colors that can be combined to make white light.
There are materials such as dyes and pigments that naturally absorb certain colors of light Main difference between the 2 is that pigments are usually made of minerals and dyes are usually plant or insect based.
Pigments that only absorb 1 color of light is called a primary pigment. The 3 primary pigments are yellow, magenta and cyan Secondary pigments then absorb 2 colors of light and are thus red green and blue
Polarization of light relates to the filtering out of wavelengths based on orientation ◦ They only allow 1 orientation to go through Thus if you place 2 polarized lenses at 90 degrees you block out all light
Like sound light also undergoes the doppler shift. ◦ Unlike sound, the V is much less than C so we can simplify the equation as follows F obs = f( 1 +/- v/c) Since most of the doppler shift of light was analyzed by astronomers, they were interested in wavelength instead of frequency Thus the equation is as follows (λ obs – λ ) = Δλ = +/- v/c λ