P 1.1 Infrared radiation Flashcards
(10 cards)
What is infrared radiation?
Infrared radiation is a type of electromagnetic radiation emitted by all objects that transfers energy as heat.
How is the amount of infrared radiation emitted affected by temperature?
The hotter an object is, the more infrared radiation it emits in a given time.
What types of surfaces are the best absorbers and emitters of infrared radiation?
Black and matte surfaces.
What types of surfaces are the worst absorbers and emitters of infrared radiation?
White and shiny (reflective) surfaces.
Can infrared radiation travel through a vacuum?
Yes, infrared radiation can travel through a vacuum.
Why can’t conduction and convection occur in a vacuum?
Because there are no particles to transfer energy in a vacuum.
What is the difference between absorption and emission of infrared radiation?
Absorption is when a surface takes in infrared radiation; emission is when it gives out infrared radiation.
What happens when an object absorbs more radiation than it emits?
Its temperature increases.
What happens when an object emits more radiation than it absorbs?
Its temperature decreases.
Why do shiny surfaces stay cooler in the Sun than black surfaces?
Because shiny surfaces reflect more infrared radiation and absorb less.
