Yes. One place in space has different temperatures. I would assume even individual particles are not distributed by a Maxwell distribution, so the concept of temperature is hard to apply. The background radiation has one temperature. If you add the sun, however, you already have a problem as the sun radiation is not in thermal equilibrium. So depending on how you look at it, you get different temperatures. The particles have a high energy, so also a high temperature. But they are so rare, that radiation is the dominant mode of heat transfer and determines the temperature of a thermometer placed in space.
lurker2718
joined 1 year ago
I think it is actually the other way around. You can consider the air inside the balloon to have internal energy from the heat. And additionally you have to make room for the balloon in the atmosphere, so you have removed the atmosphere from the volume the balloon takes, which also needs energy. If you consider both you arrive at the concept of enthalpy (H = U + pV), which is very useful for reactions in the atmosphere as pressure is constant. For this example it is not that useful as outside pressure changes when the balloon rises.
Another way to see it, the pressure has no "real" energy. In a ideal gas, the only energy comes from the kinetic or movement energy of the atoms. Each time a gas molecule is hits the balloon envelope it transfers some momentum. The cumulative effect of the constant collisions is the pressure of the gas. If the balloon is now expanding slowly, each collisions also tranfers some energy, in sum building the work the system has to do to the atmosphere. Leading to a decrease in internal, so "real" energy in the balloon. This corresponds to a decrease in temperature.
The stratosphere is heated not by the ground but directly from solar radiation leading to higher power input at the upper layers. So the top is hotter and now convection never starts and you get no cooling of the air when rising.
While I agree in general, one point is a bit to simplified in my opinion
In other words, there are fewer air molecules per cubic foot (volume of air). The molecules are farther apart and can hold less heat energy. Because "heat" is what we say when we mean molecules are moving around.
Less molecules mean less heat, it has nothing to do with the temperature, if you just decrease the density by removing half the molecules, you have the same temperature.
It cools down because it expands adiabatically. Consider a very thin balloon filled with air which is warmer than the surrounding. This now rises up, but as it does, the pressure decreases, causing the balloon to expand. During this expansion, the balloon transfers energy away from itself, because it has to push away air, to make room for expanding in the surrounding. This work cools the air inside the balloon. Assuming the air inside is dry, it would cool around 10 °C per km it rises. Now if you think about it, the balloon just stopped the inside from mixing with the outside. If you look at a large "piece" of air, it does not mix very fast, so you can remove the balloon and just consider what happens with warm air heated from the ground.
Now this does not mean, it has to be cooler when higher up. The same points hold, inside a house, but there it is often warmer when higher.
The best explaination is when looking where the heat comes from and goes too from the air. The atmosphere is mostly heated from the surface of earth, so the bottom and cooled from the upper layers. So naturally it gets hotter where it is heated. The question is now by how much? There are three modes of heat transfer in the atmosphere: radiation, conduction and convection. The first two are very slow. Connection is fast but has limits. Consider the piece of air, if it rises, it cools. So at some place it may be the same temperature as the surrounding air, so it stops rising. This means the convection works only when the air gets cooler by 10 °C/km going up (~6.5°C when the air is moist and precipation happens). So this temperature gradient is observable very often.
Yes, the file itself (so the data and inode) is not gone as long as the handles live on. Only the reference is gone. You canstill recover the file. https://superuser.com/questions/283102/how-to-recover-deleted-file-if-it-is-still-opened-by-some-process#600743
Ja das stimmt, da hab ich aus der Physik kommend zu anwendendunsorient gedacht.
Aber für die Frage ob komplexe zahlen gebraucht werden, reicht es, eine isomorphe alternative zu haben. Die komplexen Zahlen haben auch nicht mehr mit Quantenmechanik zu tun wie die Matrizen, nur sind sie leichter handzuhaben.
Die gesamten 2x2 R Matrizen nicht, aber es gibt eine Untermenge die ein Körper ist und isomorph zu C. Nämlich alle die sich durch Linearkombination der Einheitsmatrix und der Rotationsmatrix um 90° ergeben.
Also a+ib ~ [[a, -b],[b,a]]
https://math.stackexchange.com/questions/1028371/complex-number-isomorphic-to-certain-2-times-2-matrices#2644514
But also learn to feel your feelings by yourself.
I agree completely with this stance
If you need to talk a lot about your feelings, especially the deep stuff, talk to a therapist. That’s not brushing you off, it’s what therapy is for.
While I agree that therapy can help a lot in those situations, I don't think these talks should be limited to a therapist. I try to be somebody you can come to and talk about deep stuff for my friends. With one friend of mine, I mostly talk about deep feelings. It is great to have somebody like her, it's a different category than therapy. A therapist shouldn't give you his opinion and rarely shares similar experiences. Sometimes it's just nice to have someone to talk to in a more symmetric way. For me it's almost never a burden to listen to the emotions of people I like. I want to hear the deep stuff.
Sure a friend is not a replacement for therapy, but therapy is also not a replacement for a friend with whom you talk about deep emotions.
This hits me hard. I am a cis male and currently trying to get rid of something like toxic masculinity, but as you say it is deeply rooted.
I acually never strived for the stereotypical man image, I wanted to have an emotional side. Now i know i always just considered "having am emotional side" just as another kind of requirement to be a good man. So i tried listening to others and beeing open myself, talking about emotional things. But only those, that i thougt were accepted. I never talked about my real worries. They always seemed to ridiculous to me. A good emotially healthy man shouldn't have them or solve them himself. Now it feels pretty dumb in retrospect, but I am no longer letting this feeling stop me from talking about something. In some way I also have the feeling i betrayed other people with a fake personality.
I know this is not the mistake of feminism. I cannot really say what went wrong to land in this position. I do not even know why i tell this now. In some way, I just want to tell my story and hope someone can relate with it. Secondly i want to say, that the following is not obvious for everyone, at least it was not for me: Beeing emotional is not just some requirement for you, it's also about having an opportunity to get support for your worries.
I just want to say, i loved Dragon's Egg for this level of detail to the physics. I even did some quick calculations why you want 6 compensator masses not less to reduce the effect of tidal forces. Or the black holes inside the sun, at first i thougt, this is impossible. Then i read some more on it an noticed its well researched.
Dann sind aber die Effekte durch Windräder und Katzen auch nicht vergleichbar, die treffen nämlich sehr unterschiedliche Arten.
Insofern ist der Vergleich mit Hühnern auch nicht schlechter als so.
When there is only 50% totality, photovoltaic also makes 50% less. You just do not notice it when looking around, because your eyes adjust to the changed brightness. So a photovoltaic produces less for a longer time. What I found, for the 2017 eclipse, was that around 16GW were impacted with at most a reduction of 5GW in one moment.