U.V. Rays

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U.V. Rays

• Eliza Burr, Sydney Appelbaum, and Brittany
  Tedford-Riley

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What Are U.V. Rays?

• U.V. (or Ultra Violet) Rays are what comes from
  the sun, what causes our sunburns, what helps
  bees pollinate.

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What Are U.V. Rays?

• U.V. Rays lie between Visible Light waves and
  X-Rays on the Electromagnetic Spectrum.

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What are U.V. Rays?

• The wavelength is between 4x10-7 meters and
  1x10-8 meters.
• The frequency is between 1015 Hertz and 1017
  Hertz.

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How Were U.V. Rays Discovered?

• Discovered in 1801 by Johann Wilhem Ritter.
• Ritter was born on December 16, 1776 in Samitz,
  Germany.
• While doing an experiment with silver chloride,
  Ritter found that it was darkened by a substance
  beyond visible lightUltra Violet Light.

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How Were U.V. Rays Discovered?
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Types of U.V. Rays

• UVA
• very similar to visible light
• is the most harmful to the eyes
• UVB
• wavelength is 2.8x10-7 meters to 3.15x10-7
  meters
• Causes tans and most skin damage, including
  cancer
• UVC
• wavelength is 1x10-7 meters to 2.8x10-7 meters
• Earths atmosphere blocks most of these, but they
  slowly deplete the ozone
• Most harmful type

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Types of U.V. Rays
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Who Can See U.V. Rays?

• Humans cant see them
• Some insects can see them and often mistake them
  for the suns rays.
• Bumblebees use U.V. Rays to find pollen in flowers

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Uses for U.V. Rays

• Forensics identifying bodily fluids
• Florescent lamps
• Helps make Vitamin D for bones
• Treats skin diseases such as psoriasis, lupis
  vulgaris, and tuberculosis
• Kills bacteria
• Dental practices helps glue dryMinerology
  identifies minerals
• Detects forgeries in artwork
• Astronomy can identify planets and stars
• Ultra Violet fly traps

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Uses for U.V. Rays

• Dental Practices

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Are U.V. Rays Harmful?

• U.V. Rays make up 7 of the sun, but only half
  that reaches the earth
• If all the U.V. Rays in the sun reached earth,
  they could kill living things
• Sunburns are caused 15 minutes after exposure to
  UVB rays
• Can cause wrinkles, melanomas, and damage
  cataracts

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PROTECT YOURSELF USE SUNSCREEN