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1

A force does not require a constant input of energy to exist. Energy is only required to perform work, which is exerting a force over a distance. $$ W = \mathbf F \centerdot \Delta \mathbf x $$ That distance is key. In your example, if the size of the container does not change, no energy is expended no matter how long the force lasts. If the force is used ...


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As long as the outlet tube has greater vertical depth than the inlet tube, the weight of falling gas in the outlet tube should maintain an area of decreased pressure at the top of the siphon which should keep the gas in the inlet tube from sliding back into the source pool, and a flow should be maintained. I don't see why this wouldn't work. The Wikipedia ...


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Issues with that derivation: You're missing the extra term $\frac 52 k N,$ which may matter if you have to do any work with chemical potentials. Your students will not necessarily know why to parcel the space into volumes of size $\lambda^3$. Starting from the definition of entropy and deriving that the thermal volume $\lambda^3$ is important seems ...


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I posted the following solution on this board wanting to get opinions of the validity of a solution using only the microcanonical ensemble: Simpler derivation of sarkur-tetrode equation I still haven't received any comments, but if you have any, feel free to chime in. The Sarkur-Tetrode equation is the following without the 5/2 constant term: $$ kn \ln ...


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In addition to the other reply, it can be added that by definition, in an ideal gas, there is no interaction between molecules, and therefore no potential energy associated with the average distance. This is why in a Joule-Thomson expansion, there is no change in the temperature of the gas: only the volume changes, no work is extracted, and the average speed ...


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The internal energy of an ideal gas is independent of volume when considered as a function of volume and temperature. If we choose to consider internal energy as a function of volume and some other thermodynamic variable we will find that the dependence of the energy on volume will change because we are keeping a different variable constant as volume is ...


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The boiling water will boil at a constant temperature. As long as the can is in the boiling water, you will not need to worry about the temperature of the stove. If this experiment is run at sea level, and you are using pure water, the can will remain at 100 deg C throughout the experiment. If you are at an elevation higher than sea level, and you want to ...


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OK the first thing to notice is that in a gravitational field the pressure of a gas is not constant, but decreases with altitude. This means simply asking "what happens when we change the volume of the gas?" is not a well defined question; the amount of work done in the expansion is going to depend on exactly how we change the shape of the container. We ...


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Peter Solo, it looks like you are posting an engineering question related to the equipment that you see on your job. Most employers (all that I have ever encountered) consider such information to be proprietary, and in my opinion, you are "walking on thin ice" regarding the engineering ethics and legality of the situation, because such information should ...


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I guess one reason why pressure and flow rate entering the compressor may vary is gas liquid contents vary, liquid is separated in the suction scrubber, so when more liquid is separated the less is pressure and flow rate at the compressor inlet.


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"Thermal energy" is a bit of a misnomer because "thermal" really refers to a method of energy transfer, not energy storage. When energy moves from one system to another, it can do so via a thermal process (e.g. conduction, convection, radiation) or a mechanical process (something pushes on something else). So technically, I wouldn't call $\frac{3}{2}kT$ the ...


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Hopefully, I will not be "bad mouthing" those who have a background similar to my own, but here goes. In the world of chemical engineering, there are quite a few equations that are much more empirical than "first principle" based. This is particularly true for heat transfer problems, which usually have to deal with turbulent fluids. From a practical ...



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