The thermal conductivity of a material is a measure of its ability to conduct heat.
Questions tagged [thermal-conductivity]
606 questions
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Why don't you get burned by the wood benches in a sauna?
When you go to the sauna you may sit in a room with 90°C+. If it is a "commercial" sauna it will be on for the whole day. How does it come that when you sit on the wood you don't get burned?
I believe this question is different than the "classical"…
famfop
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Why does cold metal seem colder than cold air?
(I apologize for this elementary question. I don't know much about physics.)
Let's say that I put a metal pot in the refrigerator for several hours.
At this point, I guess, the pot and the air (in the refrigerator) have the same temperature.
Now, I…
Niccolo M.
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Does anything in an incandescent bulb actually reach its color temperature (say 2700 K)?
This question is inspired by a question about oven lightbulbs over on the DIY stack. It spawned a lengthy comment discussion about whether an incandescent lightbulb with a color temperature of 2500 K actually has a filament at a temperature of 2500…
Bear
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Why are steel thermal mugs much better than plastic ones?
I have several thermal mugs, two of them by the same brand, have the same look, shape and size except that one is in steel (inside and outside) and the other one, plastic. Both have an insulating layer of air or vacuum.
I do not need a thermometer…
37
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4 answers
Why do we need insulation material between two walls?
Consider a slab made of two walls separated by air. Why do we need insulation material between the two walls. Air thermal conductivity is lower than most thermal conductivities of insulating material and convection cannot be an issue in the enclosed…
Shaktyai
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Does an empty refrigerator require more power to stay cold than a full one?
Given that everything else is equal (model of fridge, temperature settings, external temperature, altitude), over a given duration of having the door closed, does it require more electricity to cool an empty refrigerator AND maintain that…
trpt4him
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8 answers
Are specific heat and thermal conductivity related?
Are there any logical relationship between specific heat capacity and thermal conductivity ?
I was wondering about this when I was reading an article on whether to choose cast iron or aluminium vessels for kitchen.
Aluminium has more thermal…
Vinoth Kumar C M
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8 answers
Why does holding a hot object with a cloth make it feel less hot?
Let's say that I held a hot object with a warm cloth. It instantly feels less hot and only warm to the touch. This is because the cloth is an insulator and doesn't allow as large a heat transfer as if I held the object with my bare hands.
However, I…
Oion Akif
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6 answers
How does fire heat air?
I understand that fire heats its surroundings via conduction, convection and radiation. I've read that conduction is nearly irrelevant to this process as air is a poor heat conductor. In descriptions of convection, people often just say "fire heats…
katefull06
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Can you model cold as flowing?
Obviously, cold isn't a "Thing".
Coldness is the absence of heat, and when you add a cold ice-cube to a drink there are no particles of "coldness" flowing into the rest of the drink cooling it down - the heat of the rest of the drink (in the form of…
Brondahl
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Why does water feel cooler than air?
My first assumption was based on "evaporation causes cooling" but I realized that it is not the case as it is cooler even if I am submerged under it. Are all liquids generally cooler than air ?
Just curious.
H G Sur
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Which would melt faster on the sidewalk, equal volumes of snow or ice?
Whilst walking back from class, I noticed the piled snow on the sides of the street still hadn't melted after a week despite it being sunny and generally warm $(15°C-18°C)$. "If that snow was ice, surely it would've melted away by now", I thought. I…
HsMjstyMstdn
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Why is the ground warm during winter and vice-versa?
I was just looking at the geothermal house heating in Iceland, and came to know that in the winter the water is warm, hence cools the house, but how is it hot, not about us feeling it.. My question is not why we feel it warm, but why is it warm?
I…
DEV17
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3 answers
Cooling down a container in outer space
If I have two containers filled with very hot water(~210°F) with one in outer space and one on earth, which one has a higher rate of cooling initially? Imagine the containers are single wall metal containers that are able to withstand any…
cspirou
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LED Thermal Modeling (How to solve heat equation with constant heat source)
I have a mechanical design with LEDs that generate heat. I want to estimate the temperature at the LED junction vs. time, but especially at steady state.
Knowing the LED voltage drop and current, I can estimate the power dissipated via heat (some…
Patrick
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