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Joined 1 year ago
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Cake day: November 11th, 2024

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  • So anyway a throttling process, also called a Joule-Thompson process, is a thermodynamic process in which a fluid is forced through a restriction without heat transfer and experiences a drop in pressure. Since there is no loss of energy from the fluid it’s specific enthalpy is conserved, which is interesting because it can result in counterintuitive effects in real fluids. In an ideal gas the temperature on either side of the restriction is constant, but in real fluids the temperature would go up or down depending on the properties of the fluid. Pure helium is a strange gas in this process, experiencing an increase in temperature after a throttling process, which feels counterintuitive because you’d expect most gases to get colder when they expand. If we examine the mathematical definition of specific enthalpy we see that it is

    h = u + pv

    Where h is the specific enthalpy (in Joules per kg), u is the specific internal energy (in Joules per kg), p is the pressure (in Pascals), and v is the specific volume (cubic meters per kg, equal to 1 over density). If the enthalpy is held constant while the pressure decreases, either the specific volume must increase or the specific internal energy must increase or some combination of the two. The specific internal energy is closely related to the temperature, so in some sense the temperature of the fluid after the throttling process is related to how much it expands when the pressure is released and how specific internal energy is related to temperature. For pure helium it does expand as the pressure is reduced, but it has so little energy storing capacity it gets warmer at the same time! Of course this depends on the actual pressures and temperatures, so it doesn’t always work out this way. Other fluids that get hotter like this are generally incompressible liquids, so it’s pretty weird that helium does it at all. Isn’t that neat! Physics is so cool.


  • I’ve never thought about it this way before but it makes a lot of sense. I definitely feel injustice as distinct from anger, to the point of having completely different physical sensations. Injustice to me feels like, idk kinda like I’m pissed off medusa. I feel it like the hair on my head all wants to stand up all at once and I feel this hard focus and a feeling I need to do something about it. Anger I feel much more in my face and chest kinda.






  • I totally agree. There needs to be some financial mechanisms for keeping people from becoming insanely wealthy coupled with financial mechanisms preventing people from becoming impoverished. The obvious solutions are taxes that increase with income and wealth along with UBI that someone can reasonably live off of. All of this requires regulation and strict enforcement of tax laws, especially for the most wealthy. The rich know this and actively work against it. Probably the most effective method has been for them to buy up all the mass media and pump out capitalist and anti-intelectualist propaganda. We can’t change anything if half the people drank the coolaid and actively fight against their own interests and for the interests of the rich. I don’t know how bad things will have to get for those people to wake up. Hopefully not much worse but at this point I’m afraid it might take a real civil war for things to change, at least in the USA. Possibly even a world war with how things are going. We’re already barreling towards that cliff with the federal governments foot on the gas… I just hope I live through it.







  • Can they run 24 hours too? I can’t tell you how fucking annoying it is doing something fun with friends that goes late and have to leave at god damn 11pm or some shit so I can catch the last fucking train for the night or have to sleep over. Also cars specifically for people who need to move large objects or all their worldly possessions or something.








  • Giant cat, the size of a grizzly bear, but somehow with the proportions of a chubby house cat. It’s primary prey is mega rich humans. Continuous exposure to greed in such humans lends their flesh an exquisite and deeply savory scent and flavor that the cat can smell from hundreds of km away. Like all cats they take pleasure in toying with their prey, refining their technique and cunning by repeatedly capturing billionaires, then letting them just barely escape, only to hunt and catch them again, until the thrill of the hunt or hunger overcomes them, or their toy succumbs to the chase. Friend to the destitute, the homeless, the impoverished, and all the proletariat. The cat is gentle and loving to all who respect it and want not for the fruits of others labor.