Tagged Questions

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Why can I calculate the value of an energy quantum of an Einstein solid at half the equipartition value of the heat capacity?

The energy quantum of an Einstein solid (in the limit of classical mechanics for one dimension, disregarding internal structure) can be calculated by estimating the value of $kT/\epsilon$ when ...
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Followup to: The relation between energy quanta of an Einstein solid and the equipartition value of heat capacity

As a followup question to this question: The relation between energy quanta of an Einstein solid and the equipartition value of heat capacity and this answer ...
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The relation between energy quanta of an Einstein solid and the equipartition value of heat capacity

Consider an Einstein solid with quantized energy values $U=q\epsilon$ and $N$ oscillators. I calculated some values of an Einstein solid numerically through a function in R (at the bottom of the ...
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What are the thermal properties of a “perfectly rigid” container?

can a "perfectly rigid" container be a diathermal boundary? I checked the wikipedia article for heat and read: Kinetic theory explains transfers of energy as heat as macroscopic manifestations of ...
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Thermodynamic potentials: Demonstration [on hold]

I must prove whether the statement on bold is true or wrong. Under it there is what I tried, but it does not convince me. I use one maxwell relationship on the latest line. And I take advantage of ...
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How to solve this steady flow problem? [closed]

Consider a steady Flow of air through a insulated porous plug. Air enters the plug at 100 kPa and 150m/s and leaves the plug at 50 kPa. Assuming air to be ideal gas and neglect potential energy ...
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A problem of thermodynamics [closed]

A lake is covered by a block of ice 10 cm thick. The water temperature is 0ºC and -5ºC for the air above. Calculate the ice growth rate of the block dx/dt knowing that the latent heat of fusion is ...
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Quadratic versus other types of degrees of freedom

In my text book I have the following question and after thinking about this one for hours, I can't figure out what they're getting at: In Section 2.5* I quoted a theorem on the multiplicity of any ...
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Partial Pressure - Which solution is right?

Question: Carbon dioxide (1.100 g) was introduced into a 1.00 L flask which contained some pure oxygen gas. The flask was warmed to 373 K and the pressure was then found to be 608 mmHg. If CO2 and O2 ...
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Irreversible work

I'm having some trouble trying to find the irreversible work done by a perfect gas when expanding. I know that the reversible work is greater than the irreversible one, but how can I find the ...
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Problem regarding heat engines [closed]

We have two different set ups: A 200K brick in a 300K environment A 300K brick in a 200K environment From which one of these can you extract more work? Assume equal mass and heat capacity. Using ...
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Calculating height and evaluating the vicinity of a peak in a multiplicity function for a two-state paramagnet

I have to calculate the height and width of the multiplicity function for a two-state paramagnet. I'm supposed to do this analogously to the method in the text book, which I will try to outline below. ...
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Heat transfer to a cube from one of the faces [closed]

Heat Flux= 10 MW Inlet water temperature = 28 degree centigrade for cooling purpose through a tube passing through the centre of retangular block of length 50 mm,height 30 mm and width 30 mm inner ...
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Entropy of a two-level system

Consider a two-level system with energies and degeneracies $\epsilon_0 = 0, g_0=1$ and $\epsilon_1 = \epsilon, g_1=4$. I can show that the temperature at which both levels are equally populated is ...
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Gas pressure and centrifugal force

I think about a rotating torus (simplified tire) filled with ideal gas. Mass of gas is $m$ and molar mass is $M$. Pressure in non rotating torus is $p_0$. Temperature is constant $T$. Inner radius of ...
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Supercritical Steam Expansion [closed]

Ten kg of steam at 500 bar is expanded at constant pressure until its volume increases to seven times its initial value of 0.01 $m^3$. (a) Calculate the initial and final temperature of the steam ...