Heat cannot readily escape a termos bottle, so hot things insede stay hot.?

Question

Will cold things inside a termos bottle likewise stay cold? Explian.

Answer 1

Yes, anything inside a vacuum flask is virtually sealed off from all other sources of heat, by the vacuum between the inside and outside layers of the flask, because heat loss due to conduction is prevented. There is a tiny heat transfer by radiation, but it's negligible because only very hot things radiate efficiently. So radiation loss from ice-water is teeny.

So nothing comes in, to heat it, -if it's cold, (like ice) and no heat escapes by radiation or conduction (or convection) if it's hot (like hot coffee). So it stays the same temperature inside the flask.

It's nothing to do with the layer of air inside or outside, or around the metal insert.

Answer 2

Cold things stay cold and hot things stay hot. There is a layer of air around the glass or metal insert that keeps it insulated.

Answer 3

yes the cold things also stay cild the same way as the insulating material does not allow any heat to enter from outside too.

Answer 4

Yes. It keeps hot things hot, and cold things cold.

But how does it know?