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It is especially designed to reduce heat transfer through conduction, convection, and radiation. A vacuum between two layers reduces the heat transfer through conduction and convection; the fact that the surfaces are mirror-coated also reduces losses through radiation.
Wiki User
∙ 13y ago
Wiki User
∙ 11y agothis is mainly a physics qns on heat transfer. heat can be lost in 3 ways, conduction, convection and radiation. conduction is heat transferred via contact with a solid, convection is heat transfer through liquids or air and radiation is heat transfer via energy (mainly infra-red).
A thermos flask is made to reduce heat loss via each of the 3 above mentioned ways of heat transfer. if u can obtain the image of a normal thermos flask, the 1st thing u can see is that the body and cap of the flask is hollow. this hollow area is actually vacuum, meaning it's empty, not even air occupies it. while this minimizes heat loss via convection and conduction, this however does not prevent heat loss via radiation since energy doesn't require a medium to travel. now if u open up the thermos flask n look at the interior, u realize it's a mirrored surface. based on the physics text, shiny and silver surfaces absorbs and radiates heat poorly. this is why the interior surface is shiny and is silver. this usually is on both sides of the hollow area (vacuum) of the thermos flask.
with a combination of these factors, this is why a thermos flask is able to retain heat for extended periods of time.
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How do you heat a thermos?
I put hot water in the thermos and let sit for a few minutes until inside gets hot.
Why is fiber glass a good insulator?
it traps air between the fibres so the heat can't escape. it is good for lofts because it doesn't let water pass through, support vermin, or let fungi mould and bacteria grow
Why is wood a good insulator?
It doesn't let heat through and it doesn't melt. It is hard to get electricity through which is good because it means it doesn't let heat through. It can let sound through but not heat.
Why are feathers poor conductors of heat?
They were dezined by nature to keep heat in. But if you have ever picked up a duck you would notice it is warm to the touch. Therfore it does conduct some heat. But doesnt let that much escape. Have you ever seen a car radiator or the back of an air conditioner? Thoes little strips of aluminum that look funny if you smash them together? That does not allow heat to easily disperce. Now look at a feather and get back to me.
Which material will let heat through?
Thermal conductors let heat through. These tend to be metals, such as aluminium or iron. Bad conductors might be plastic or glass.
What is the thermo flask?
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.
How do you heat a thermos?
I put hot water in the thermos and let sit for a few minutes until inside gets hot.
Why are shiny outer surfaces needed in a vacuum flask?
The outer surfaces do not need to be shiny. The interior ones do, to reflect heat back rather than let the heat pass out of the vacuum flask. The vacuum between the double walls of the flask also reduces heat loss.
Why should the distilling flask be filled to no less than one thirds of its capacity?
If the neck of your flask is short, you don't want to fill the flask too high (more than about 1/2), or else liquid from the flask will enter your distilling tube and get distilled out when you heat it. Remember the idea of a distillation is to heat up your substance to the vapor phase and let the vapor diffuse toward the distillation tube so that only purified product drips into the collecting flask.
Examples of air exerts down ward pressure?
1. Put a little water (about 20 ml) in the flask and heat it to a boil. 2. Let the water boil vigorously for at least one full minute. 3. Take the flask off the hot plate and immediately place the balloon with the mouth over the flask's mouth. 4. Let cool slowly at room temperature (the balloon will be pushed inside out into the flask).
What properties do good calorimeter have?
Well one that doesnt leak and let heat escape
What mechanisms do dogs use to keep cool?
they do not sweat, they release heat by opening their mouth and breathing heavy to let the heat escape thru their mouth
Why are pie shells pricked thoroughly with a fork before baking?
so that the heat can be let inside, and so the juice can escape the crust
What happens when you mix red phosphorus Iodine crystals and ephedrine?
You get meth in about 40 minutes. Throw it all on one flask and let it sit for a while shake the flask it if starts to bubble up too much. Then when it calms down heat it to about 180f until it doesnt look like anything else is happening.
What the uses of flask?
Flasks are usually flat round bottles carried in ones pocket. Let's say someone asks for a drink " Does anyone have a flask of brandy?"
How is the greenhouse effect the cause of the ozone layer depletion?
The greenhouse effect causes ozone depletion. Greenhouse doesn't let the heat escape, causing problems for ozone.
Why is fiber glass a good insulator?
it traps air between the fibres so the heat can't escape. it is good for lofts because it doesn't let water pass through, support vermin, or let fungi mould and bacteria grow
