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Joined 1 year ago
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Cake day: February 1st, 2024

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  • While neat, this is not self-sustaining — it’s taking more energy to power it than you’re getting out of it. (You can build a fusion device on your garage if you’re so inclined, though obviously this is much neater than that!)

    One viewpoint is that we’ll never get clean energy from these devices, not because they won’t work, but because you get a lot of neutrons out of these devices. And what do we do with neutrons? We either bash them into lead and heat stuff up (boring and not a lot of energy), or we use them to breed fissile material, which is a lot more energetically favorable. So basically, the economically sound thing to do is to use your fusion reactor to power your relatively conventional fission reactor. Which is still way better than fossil fuels IMHO, so that’s something.



  • The amount of money you save (and invest) isn’t accurately depicted with this though. Living expenses don’t necessarily grow with take home, if you keep lifestyle creep to a minimum.

    So what this means is that if you make $100k and save $10k/year, if you start making $200k you can save the same $10k/year, plus the entire additional $100k after taxes (let’s just say that’s $50k+). So you doubled your salary but your savings went up 6x+.




  • qjkxbmwvz@startrek.websiteto196@lemmy.blahaj.zoneglow rule
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    5 days ago

    “Chain migration” is how many people — myself included — get jobs.

    I went to a very good school, and while I like to think the quality of education is what makes a school “good,” let’s be honest — the value is largely in your connections. Friend lands a good job, recommends you when there’s an opening, and bam, you’re already at the top of the pile of the CVs (better yet, they’re the hiring manager).

    Friends from school — peers and mentors alike — are a great place to start, if you can. Ask to grab a coffee and chat about their career, and be clear that you’re in the market. Most people are happy to chat (at the very least, it’s flattering).

    It’s the way the world works…











  • Is that true though? As in, is it really that dangerous? It seems that you’ll dissipate power equal to the inefficiency times the nominal charging power, so something like 5V x 2A x inefficiency (inefficiency being 1-efficiency), which will probably be of order a watt.

    I can use my car battery to charge itself without any issues — I just plug the red terminal to itself, and same with the black, which is to say, a battery is always connected in a way that “charges itself.”

    I think the key is that the battery probably isn’t really playing a big role in OOP’s setup — electricity doesn’t “go through the battery,” it just goes from the charging input to the power output circuits, with the additional power (due to inefficiency) being provided by the battery.


  • I’m not sure though — the power output and the charging input are both regulated and (almost certainly) current limited. So I think (not positive…) that you’re basically dissipating your power in the inefficiency the charging and output circuits, with this power coming from the battery.

    The inefficiency should (I think…) just be the round-trip inefficiency of the charging/discharging of your power bank — this should be way, way less than the short-circuit power dissipation.

    The simplest toy model is to take a battery and try to charge itself. So you put jumpers on the + terminal and you connect those to the + terminal, and same for - (charging is + to +, NOT + to -). But this is silly because you’ve just attached a loop of wire to your terminals, which is equivalent to doing nothing. With charging circuits in between things get much more complicated, but I’m not sure if it goes full catastrophic short…