how does it know?

Question

u put hot stuff in a thermos and the stuff stays hot. u put cold stuff in the thermos and it stays cold, how does it know?

Answer 1

It's smarter than us.....actually the design just insulates the temperature of the liquid put in it.

Answer 2

It doesn't know. All the thermos is doing is limiting heat transfer through the walls of the thermos. That lets the fluid inside the thermos keep its temperature nearly constant for a long period of time (whether the temperature is hot or cold).

There is a very lengthy explanation at the following website:

Answer 3

Same way boiling coffee or ice water can be held in a Styrofoam cup and not be felt by the hand holding the cup. It insulates and allows large temperature differentials without allowing thermal energy to pass.

Answer 4

I don't know, there's just something about the way it's made or the stuff used to make it. I hope someone can tell you exactly how but it's not me!