n radiation, heat is transferred from an object to its surroundings in the form of EM radiation, usually infrared (IR) radiation.

T is the temperature on the "absolute temperature scale"

T is measured in Kelvins.

e is called the "emissivity" and depends upon the surface; we will usually take e = 1.

is called the Stefan-Boltzman constant; = 5.67 x 10 - 8 W/m2 K4

A stove emits more heat than it absorbs --

A pan, inside an oven, absorbs more heat than it emits --

Thermos Bottle

Greenhouse Effect

   Click here for an EXAMPLE.

   Click here for an EXAMPLE.



Return to ToC, Heat Transfer

(c) 2002, Doug Davis; all rights reserved