today
1 p.m. Pet Photos with Santa "Claws" Henderson Center
read >4 p.m. Young Parent Support Group College of the Redwoods Kinship Site
read >4 p.m. Teen Writing Group Ink People Center for the Arts
read >6 p.m. The Tumbleweeds Chapala Cafe
read >6 p.m. Blue Lotus Jazz Libation
read >6 p.m. State of the Watersheds Bayside Grange
read >6:30 p.m. The Transgender Day of Remembrance Humboldt County Courthouse
read >7 p.m. John Ludington + Chris Parreira + Colin Begel (acoustic) Mosgo's
read >7 p.m. Peppino D’Agostino Mateel Community Center
read >7:30 p.m. A Commedia Christmas Carol Carlo Theater (Dell'Arte)
read >8 p.m. Humboldt Folkdancers Arcata Presbyterian Church
read >8 p.m. John Ludington + Scott Garriot + Chris Parreira (acoustic) Mosgo's
read >8 p.m. Stones in His Pockets Arcata Playhouse
read >8 p.m. A Christmas Carol North Coast Repertory Theater
read >8 p.m. Keller Williams (sound) Humboldt Brews
read >8 p.m. Air Supply ('80s soft rock) Cher-Ae-Heights Casino
read >8 p.m. KJNY 3rd Annual Glow Party Arcata Community Center
read >9 p.m. NightHawk WAVE @ blue lake casino
read >9 p.m. The Melodramatics (ska) Central Station Cocktail Lounge
read >9 p.m. Cadillac Ranch Six Rivers Brewery
read >9 p.m. DJ Touch Pearl Lounge
read >9 p.m. Bondage Bash Aunty Mo's Lounge
read >9 p.m. Latin NIght The Red Fox Tavern
read >9:30 p.m. Phil Berkowitz & Dirty Cats (blues) Riverwood Inn
read >9:30 p.m. David Starfire Arcata Theater Lounge
read >10 p.m. Music by DJ Sidelines
read >10 p.m. DJ Ninja Retro Dance Party Aunty Mo's Lounge
read >10 p.m. SexyTime: MiMosa and Sleepyhead Mazzotti's Arcata
read >previous columns
May 29, 2008
Fossil Collagen
Collagen is the protein that holds our bodies together. It ...
read >May 22, 2008
Pumping Heat
If you own a refrigerator, you own a heat pump, ...
read >May 15, 2008
Fossils Alive
Living fossils" are living species that resemble ancient fossils. In ...
read >Photos
Polarized
By Don Garlick
If you wish to see submerged rocks ahead, or creatures in a tide pool, you need to wear Polaroid sunglasses. Their ability to reduce glare is a consequence of some very interesting physics. I will demonstrate, for example, that when you see light reflected from a surface, that light did not simply bounce off the surface. The light you see was actually produced by vibrating electrons within the illuminated liquid (or solid). Those electrons were made to vibrate by the primary light, and the vibrating electrons radiated secondary light which entered your eyes.
Light consists of electromagnetic waves, but we can here ignore the magnetic part. A light ray consists of countless individual photons with each photon's electric field oscillating at right angles to the ray (Diagram A). If the ray is polarized, all the photons share the same direction of oscillation. Unpolarized light is oscillating in all possible directions.
Consider unpolarized light illuminating water (Diagram B). At a certain angle your Polaroid glasses will completely block the reflected ray! That ray is perfectly polarized, and it departs the water at 90 degrees to the refracted ray! The explanation lies in the fact that electrons within the water molecules are induced to vibrate parallel to the electric fields of the refracted ray. Furthermore, electrons cannot radiate light in the direction of their vibration. Only those vibrations which cross your line of sight can yield light that enters your eyes. Hence, your eyes receive horizontally polarized light which will be blocked by Polaroid sunglasses. Although reflected light may appear to bounce off the water's surface, and you may see an image of the light source, the light actually originates from a thin layer of water near the surface. Interference between adjacent rays prevents radiation from below that thin layer.
Ladies, if your man declares that your skin is glowing or your hair is shining, he is really telling you the truth: Your electrons are visibly jiggling.






















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