If you filled a black can and the shiny can with hot water, and put them in a cool place what would cool first

Question

i have to answer this question for a science assignment and i am not to sure on the answer

please help me?????

Answer 1

This question just bugs me because there isn't enough information.

If the black can is rubber and the shiny can is metal, then the shiny can will cool first because rubber is a good insulator and metal is a good conductor of heat.

Also, if they are both basically the same substance, but that cool place happens to be in sunlight, then the metal can will again probably cool faster because it reflects the sunlight while the black can absorbs it, keeping it warmer.

However, I think the answer you're supposed to give is that the black can will cool faster because black is better at emitting thermal radiation than other colors.  See "black body radiation":

http://en.wikipedia.org/wiki/Black_body

All in all, a poor question because it's so vague.

Answer 2

The black can, at least in theory.  That's why car radiators and motorcycle cooling fins and heat sinks on amplifiers are black.  Note that a black object picks up heat more readily than a shiny one, too.  It works both ways.  

In some cases you'll discover that the difference between shiny and black makes no measurable difference.  Coatings can be weird, and things that are black in visible light aren't always black to infra-red.

Answer 3

i think shiny can will cool first.