Main Question or Discussion Point
excuse me if this is too basic question. why is it that black materials BOTH "absorb" and "radiate" more heat ( energy ) and white materials do it less. i mean is there a rule that any material absorbs and radiate heat in the same amount and can't absorb more (like black materials) and radiate less ( like white materials) at the same time. i think i have seen such thing when i was in college (8 years ago and i don't have major in physics).