1/8/09
Post date: Jan 08, 2009 2:28:16 PM
Bell Activity:
Light dispersion
The index of refraction is slightly different for different colors
When different colors enter a new material (white light consists of all visible colors mixed together), they are refracted at different angles
This causes the colors to spread out, producing a rainbow of colors
Happens with prisms, water droplets
Diamonds
Very high index of refraction means a smaller critical angle, or LOTS of internal reflection
When white light enters a diamond, the light is dispersed (colors spread out).
The separated colors bounce around inside the diamond many times (internal reflection) before exiting, giving the colors more space to spread out.
This gives diamonds the "fire" we see, or the many different colors coming from a diamond's facets
Diffraction
Two-slit interference
Light goes through two openings, very near to each other
Light spreads out from each opening in all directions
The light from the first opening interferes with the light from the second opening, creating a pattern of bright and dark spots.
Page 394 for two-slit interference equation
Page 395: 1-2
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