thermal radiation

• what is thermal radiation?

  heat transfer via infra-red ray
• what kind of heat transfer happens in a vacuum?

  thermal radiation
• what is a vacuum?

  a space with no particles
• why does the thermal energy store of a hot object get less , and the thermal store of the surrounding get bigger?

  the surrounding are at a lower temperature then the object
• in what direction does thermal energy flow?

  towards area with lower temperature
• unit of temperature

  degrees celcius
• boiling point of water

  100 degrees celcius
• freezing point of water

  0 degrees celcius
• what colour materials are good radiators?

  dark and dull
• what colour materials are poor radiators?

  light and shiny
• what colour materials are good absorbers?

  dark and dull
• what colour materials are poor absorbers?

  light and shiny
• what colour materials are good reflectors?

  light and shiny
• absorbers of heat

  objects which take in heat radiation
• emitters of heat

  objects that give off heat by radiation