Visible and UV-Light Waves

• How does visible light appear different colors?

  It depends on the wavelength of light
• What is the order of colors in visible light?

  Red, orange, yellow, green, blue, indigo, violet
• What does the phrase "boy G bit" help to remember?

  The order of colors in visible light
• How do optical fibers transmit light?

  By reflecting light at the surface
• What is necessary for optical fibers to work effectively?

  Materials that totally reflect light
• What is the advantage of using optical fibers over copper wires?

  They transmit more information with less distortion
• Where does ultraviolet radiation fall on the spectrum?

  After violet light
• What is a common source of ultraviolet radiation?

  The Sun
• What is fluorescence?

  Absorption of UV light and emission of visible light
• Why do fluorescent paints appear bright?

  They emit light after absorbing UV light
• How do fluorescent lights work?

  They convert UV light into visible light
• What are the benefits of using fluorescent bulbs?

  Energy efficiency and reduced emissions
• How are security pens used with UV light?

  To mark property with invisible codes
• What is a use of UV radiation in security?

  Marking property and detecting forgeries
• What is one use of UV radiation in water treatment?

  To sterilize water by destroying microorganisms
• What are the main uses of visible and ultraviolet light?

  • Communication using optical fibers
  • Fluorescence in paints and lights
  • Security features in documents
  • Sterilization of water
• What is the difference between specular and diffuse reflection?

  Specular reflection is clear, diffuse is scattered
• How is information encoded into light pulses for transmission?

  By varying the light's intensity or frequency
• What is a common use of ultraviolet radiation in tanning?

  Sunbeds for artificial tanning