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What is the temperature of water at the end of the pipe?

I need to solve the following problem for a practical application. Water, initially at temperature $T_0$, flows with a constant speed $v$ through a PVC tube of length $l$ and diameter $D$. The ...
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Is perfect thermal insulation possible?

Supposing someone says they have a sample of insulanium with the following properties: If you make a thermos out of insulanium, it will keep a drink hot or cold forever. If you put your hand on a ...
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Calculation of temperature distribution in bulk glass due to laser heating

I'm trying to figure out how to simplify the problem where laser pulses are focused to a small spot in bulk glass. The waist of the beam is about 20 microns. At the wavelength used there is only two-...
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Question about a particular thermal shock scenario

I watched this video https://www.youtube.com/watch?v=xbuvcQrAOSk Where they heat up a pyrex pot and then add a few drops of cold water to see how the pot will react (while shooting the scene with a ...
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Will heat flow by conduction oscillate until thermodynamic equilibrium is reached in a solid object?

Consider the following thought experiment with $2$ conducting objects $A$ and $B$, where object $A$ is initially at a much higher temperature than object $B$. The objects are now placed in perfect ...
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Velocity of heat flow through a conducting bar [closed]

In thermal conduction process a heat source is connected at the one side of a lagged bar and another end is free.so after applying heat the temperature of each layer of the bar increases .if We ...
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Difference in steaming with superheated steam to saturated steam in coffee beverages

Coffee machines are emerging on the market which claim to superheat the steam they use in heating and aerating milk via a submerged nozzle for latte/cappuccino type beverages. So instead of the ...
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What is the rate of heat transfer between 25C water and 20C air?

This might be an elementary question, but I was only able to find the formula for heat transfer only in one substance. *Surface area: 1 meter square
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At what rate does a wet clothing decrease the temperature of a human body?

The question is required for my project, but it is frankly too hard for me... The variables that I consider are: Human Body: 36.5(C) Air: 20(C) Sunlight Intensity: 1,368(W/m^2) Wind Speed: 20(km/hr) (...
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Which one is better at keeping you warm? [closed]

Does Glass feel warmer during winter when you keep your feet on it or Wood?
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Why do electrically conductive materials tend to be thermally conductive?

It's hard finding substances that are good insulators of one and conductive of the other. Why the correlation? And why do some materials not have this correlation?
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Why thermal conductivity increases with temperature?

what is the molecular mechanism with which thermal conductivity increases by increasing temperature? at least for metals? I know that heat increases the oscillations of the atoms in the crystal. But ...
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Heat distribution in a long cylindrical electrical resistive element

I want to know what the maximum temperature will be within a heating element. Quite a few assumptions can be made, such as constant thermal conductivity, constant electrical resistivity, and assume ...
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Thermodynamics - Change in temperature based on time

Hello Physics Stack Exchange, This is my first post on this forum, please correct me on any semantic mistakes I may make. Recently in my physics class we did a lab on Heat Capacity, where we had a ...
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Why the 3D heat equation is $\frac{\partial u}{\partial t}=\alpha\nabla^2u$ [closed]

Why the 3D heat equation is $$\frac{\partial u}{\partial t}=\alpha\nabla^2u=\alpha\left(\frac{\partial^2 u}{\partial x^2}+\frac{\partial^2 u}{\partial y^2}+\frac{\partial^2 u}{\partial z^2}\right)?$$ ...
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Anomalous expansion of water when heated

In one question I found that when water was heated from 0°C to 15°C then the volume 1st decreases and then increases why is that so ?
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Why are wooden houses warmer than concrete ones in cold regions?

Why are wooden houses warmer than concrete ones in cold regions? I went looking for data and I saw that both have similar emissivity and similar conductivity. Thus I am confused. Moreover, the ...
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Will throwing oil on snow help it melt faster (significantly)? [closed]

The main thing that melts snow is the sun. Indeed, without the sun, the air itself would eventually turn to snow. The problem is, the sun melts snow inefficiently. The sun emits radiation (a lot of ...
76 views

Heat Losses to furnaces

I am looking in to the thermal efficiency of a furnace vessel. I am wanting to get a full, or at least better, understanding on the calculations needed to look at the thermal efficiency. So I know ...
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How is Thermal Design Power (TDP) related to Surface Power Density (SPD)

Although this question is kind of IT related I'm interested into the actual physical backgrounds and thus posting it here. I know that TDP is an indicator for dimension of the thermal dissipation ...
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When does heat conduction become convection?

Okay, I have a hard time wrapping my head around something, I think, pretty basic. For a little hobby project of mine I was making a fermentation-box for beer brewing allowing me to accurately ...
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At the lambda point, why does specific heat capacity tend to infinity?

The specific heat capacity is the energy required to raise the temperature of unity mass by 1K, if at the lambda point all the bosons occupy the lowest quantum state, shouldn’t the specific heat ...
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How does conduction happen?

I'd like to ask you how does conduction happen ? I mean, the atoms vibrating more hits the less vibrating atoms and gives energy. But how is that energy transferred ? For atoms to collide they must be ...
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Effect of Particle Mass on Thermal Conductivity

Fouriers law of thermal conductivity is $$\vec{q} = -k\nabla T$$ where $q$ is the heat flux, $k$ is the thermal conductivity. Mass does not seem to appear in the equation. So I'm wondering what ...
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Different results for thermal resistances using different methods

A system is set up which is composed of a cylinder with hemispheres on either ends. The length of the cylinder is l and inner and outer radii of cylinder and hemisphere are $R_i$ and $R_f$. The ...
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how can different shapes of thermometer bulbs effect response to temperature changes?

Two thermometers are constructed in the same way except that one has a spherical bulb and the one, cylindrical. Which one will respond quickly to temperature changes and why?
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What is the coefficient of volumetric expansion of water? [closed]

What exactly is coefficient volumetric expansion? Is it $\gamma\,\Delta T$? Since water has maximum density at 4 C, is $\gamma=4\,{\rm C}^\circ$?
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Is sun a black body? [duplicate]

My teacher told me that sun is a black body but after reading at various sites whre they say that sun is not a black body but has black body radiations because it cannot absorb all radiations.