infrared radiation

• Why can't the human eye see infrared radiation?

  Infrared radiation is outside the visible spectrum
• What is a Lesley's cube used for?

  To measure infrared emission from surfaces
• What surfaces are present on a Lesley's cube?

  Shiny metallic, white, shiny black, matte black
• How do you ensure repeatable measurements in the experiment?

  Keep the same distance between cube and detector
• Which surface emits the most infrared radiation?

  Matte black surface
• Which surface emits the least infrared radiation?

  Shiny metallic surface
• What is the resolution of a thermometer compared to an infrared detector?

  The thermometer has lower resolution
• What equipment is used to measure infrared absorbance?

  Infrared heater and metal plates
• What happens to the temperature of the metal plates when the infrared heater is switched on?

  The temperature increases as they absorb infrared
• What is used to attach the drawn pin to the metal plates?

  Vaseline
• Which plate does the drawn pin fall off first?

  Matte black plate
• Why do matte black surfaces absorb more infrared than shiny metallic surfaces?

  Matte black surfaces are better absorbers
• What is the effect of shiny metallic surfaces on infrared radiation?

  They tend to reflect infrared radiation