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Why is a thermos flask good at keeping drinks cold as well as hot?
Wiki User
∙ 15y ago
Because it has good insulation so it prevents boss loss and gain of heat from the surrounding ----
Well that's true, but more interestingly, it has a glass chamber inside which is smaller than the outer casing. The air between the glass chamber and the outer casing has had almost all of the air removed, and is therefore a vacuum.
This makes the heat unable to escape between the inner chamber and the outer casing, keeping the liquid hot. It also stops heat from outside being able to get into the liquid stored in the glass chamber, therefore keeping it cold.
Most of the heat from the flask is lost from the lid, since the liquid has to come out of somewhere.
Wiki User
∙ 15y ago
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What is the Functions of thermos flask with diagram?
The primary function of a thermos flask is to keep liquids hot or cold. There is an outer protective layer with a hollow area inside before the actual area where the liquid is stored. Heat or cold gets trapped in the hollow area and that is what keeps a liquid hot or cold.
Why sides of thermos bottle are silvered?
Silver is a great heat and light reflector. That means if you store cold water in a thermos, the heat from outside cannot get into the thermos easily because the heat is reflected by the silver color of the thermos.
Thermos bottles are used to keep liquid what?
Thermos bottles are generally used to keep liquid from changing temperature for a longer period of time. Usually, one pours hot liquid into the bottle, and it will remain warm for longer, but they are also effective at keeping cold liquid cool.
Is thermos a conductor or insulator?
you tell me if you fill a thermos with hot soup or hot chocolate put the lid on and then touch it is it hot or cold. odds are it is warm so it is hard to say. but the thermos is an insulator
Will a thermos keep cold or hot water at it's temperature range longer?
The rate of heat flow across a boundary such as the vacuum between the inside of the thermos flask and the ambient atmosphere is proportional to the temperature difference. So if you have hot water inside at say 90 C and an ambient of 30 C that is a difference of 60 C, whilst if you have cold water inside at 10 C the difference is 20 C. The heat flow will therefore be three times as much for the hot water as for the cold water, so the rate of change of temperature will be three times greater.
Is a thermos flask also good for keeping water cold for several hours?
Yes. The thermos flask can reduce the amount of heat travelling from the surroundings to the cold water
What can be held in a thermos flask?
Hot drinks such as tea and coffee are usually held in a thermos flask. The flask will keep the drink warm for several hours when one is outside or on the move. Cold drinks can also be kept in them or even non drinking liquids that one wishes to keep at a steady temperature.
The presence of -------------- in a thermos flask keeps the substances either hot or cold?
A vacuum is the answer.
What is A container to keep drinks cold?
A flask. It also keeps drinks hot.
What did James dewar invented?
James Dewar invented a type of thermos for keeping liquids hot or cold. James Dewar is also an inventor of smokeless gunpowder. Although, he did not invent this on his own.
What is the Functions of thermos flask with diagram?
The primary function of a thermos flask is to keep liquids hot or cold. There is an outer protective layer with a hollow area inside before the actual area where the liquid is stored. Heat or cold gets trapped in the hollow area and that is what keeps a liquid hot or cold.
Why your vacuum flask cannot maintain the cold anymore?
There could be a crack or leakage that allows air to flow in or out of the flask. It may be time to replace the flask with a new one.
What happens if a cold substance kept in thermos flask?
It heats up and the water keeps warm for a certain amount of time
Does a thermos freeze liquid?
A vacuum flask keeps hot things hot & cold things cold. Just how it tells the difference is one of the mysteries of the scientific world !
What keeps the contents of a thermos flask hot or cold?
The thermal insulation used round the container holding the food. This is normally an evacuated, mirrored, double walled glass flask with an insulated stopper.
What does a thermos do?
A thermos will generally keep either a hot item hot or a cold item cold. you can use them for things like cold drinks, soup, hot chocolate, or pretty much any liquid you want to keep the same temperature.
Will snowman with a coat or without melts first?
Without a coat the coat keeps the cold air in, like a thermos flask we learnt this in year 3....
