A flask is basically a thermos that is used to hold liquids (beverages) that are meant to be kept warm.
Thermos flask is a thermos container used to store liquids like any hot drink. The liquid added to thermos flask will retain the temperature even after some time irrespective of external temperatures.
Hot drinks are usually put in a thermos flask, so the flask needs to be made of something strong in order not to get ruined in any way, therefor steel is used.
It helps to insulate the thing inside the thermo flask. The heat or coldness outside the flask gets reflected away. It might sound silly but it is true
A thermos is able to do what it does by using a several of physical and material properties to keep our hot chocolate hot and our ice tea icy. A thermos has an inner container made of glass. This container is really like one bottle inside of another bottle and sealed at the ends by melting the edges together. The air is removed out from the space between the two bottles to produce a vacuum, which is not a good conductor of heat and does a good job at slowing down the movement of heat. To slow down the other heat they coat the facing surfaces of the glass bottles with a silvery coating (like a mirror). This reflects the heat and helps slow down any losses that might get that way. They use a material like cork or rubber to make the bottle stopper and anything else that might touch the outside surface of the glass container. These materials are bad conductors of heat and slow down the heat loss. What's left is what we can see on the outside which can be metal or plastic and is the covering for the glass bottles. The idea here (with the thermos) is to slow down the movement of heat from one place to the other. So if you have hot stuff in the thermos or cold stuff in the thermos, the end result is the same. Keep heat from moving to where you don't want it to go for as long as possible. NB It's worth mentioning that modern vacuum flasks (Thermos being a trade name) are made almost entirely of stainless steel, inside and out - it doesn't shatter and is naturally reflective, although not polished to a mirror shine when used as a flask inner. Modern stoppers are also made of plastic.
out of steel
inside a thermos is flask steel materials, it keeps the thermos for about 1 - 2 days.
The vacuum reduce heat loss by conduction and convection.
A Thermos.
Thermos flask or vacuum flask.
Yes. The thermos flask can reduce the amount of heat travelling from the surroundings to the cold water
The vacuum flask otherwise known as a thermos flask
There is air between the inside and outside of the flask.
A flask is basically a thermos that is used to hold liquids (beverages) that are meant to be kept warm.
Thermos flask is a thermos container used to store liquids like any hot drink. The liquid added to thermos flask will retain the temperature even after some time irrespective of external temperatures.
The main heat loss in a good thermos flask, is due to heat conducted through the material. (Glass or Stainless Steel). There should be little heat lost through the vacuum of the flask.
As the flask is closed air tight, no convection current is possible.