Explain why the liner of a thermos bottle silvered,and why does it have a vacuum between its two walls.
2007-03-03 16:21:51 · 3 answers · asked by auv529 1 in Science & Mathematics ➔ Physics
The color is because of the metal they use.
When something gets cold, it's because its energy has been absorbed by something external that is directly in contact with our object or solution.
The walls are vacuumed so that there's no loss of heat due to the temperature of the air that would have been within those walls.
2007-03-03 16:31:17 · answer #1 · answered by Sergio__ 7 · 0⤊ 0⤋
I think that the vacuum is due to thermal exchanges. For example, if you hold a metal bar that you dip into a freezing liquid, the molecules closest to the liquid will start giving up their energy in order to try to achieve 'equilibrium'. The process will steadily reach to the top of the bar to where you are holding. I believe that this same analogy can explain the purpose of the vacuum. If there are no molecules to give up or take on energy, then there are no thermal fluctuations.
I may be totally off, but it seems sound.
2007-03-03 16:38:26 · answer #2 · answered by ~b 3 · 0⤊ 0⤋
http://home.howstuffworks.com/thermos2.htm
Here you go.
2007-03-03 16:50:41 · answer #3 · answered by Anonymous · 0⤊ 0⤋