Visible and UV light

• What types of light are discussed in the video?

  Visible and ultraviolet light
• How does visible light appear different colors?

  It appears different colors depending on the wavelength
• What is the order of colors in visible light that can be remembered using the phrase "boy G bit"?

  Red, orange, yellow, green, blue, indigo, violet
• How is visible light used for communication?

  It is transmitted through optical fibers that reflect light pulses over long distances
• What are optical fibers made of?

  Thin glass or plastic fibers
• What is required for effective light transmission in optical fibers?

  Materials that totally reflect light rather than absorb it
• Why do optical fibers transmit light effectively?

  Because the light is reflected every time it hits the surface
• What type of reflection is necessary for optical fibers?

  Specular reflection rather than diffuse reflection
• What is the advantage of using optical fibers over copper wires?

  They can transmit much more information and are less likely to be distorted
• Where does ultraviolet radiation fall in the light spectrum?

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

  The Sun
• What is one use of ultraviolet radiation mentioned in the video?

  To give us a suntan or sunburn
• How can we generate ultraviolet radiation ourselves?

  By using sun beds
• What is fluorescence?

  A property of certain chemicals where ultraviolet light is absorbed and re-emitted as visible light
• Why do fluorescent paints look bright?

  Because they emit light after absorbing ultraviolet light
• How do fluorescent lights work?

  They generate ultraviolet radiation that is absorbed by phosphorous, which then emits visible light
• What is a benefit of using fluorescent bulbs?

  They are energy efficient, saving on electricity bills and carbon dioxide emissions
• How can ultraviolet radiation be used for security purposes?

  By using special security pens to mark property that is invisible until ultraviolet light is applied
• How are ultraviolet light features used in passports and banknotes?

  They make them harder to copy and help detect forgeries
• What is one final use of ultraviolet radiation mentioned in the video?

  To sterilize water by destroying microorganisms