• starman2112@sh.itjust.works
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    10 months ago

    A lot of people think that to get to orbit, you just have to go up, but actually you need to go sideways.

    Imagine throwing a ball that leaves a visual trail behind it. You throw it straight up, it comes straight back down and just leaves a vertical line. Throw it across the room, and it makes an arc. Take it outside, throw it really hard, and it makes a bigger arc. Zoom the camera out, and throw it so hard it goes over the horizon. It leaves a pretty long arc right? If you throw it hard enough, that arc goes farther and farther past the horizon until it misses the ground entirely and comes right back around to you. That’s an orbit!

    But that’s only part of it. You see, any time you impart force on an object in orbit, you only change its trajectory, not its current position. Since your arm is now the lowest part in the ball’s orbit, you can never raise that point above where your arm is. But you can affect the other side of its orbit–the faster you throw the ball, the higher the opposite side of the orbit gets. Let’s head up to the highest point in the ball’s orbit, and give it another push. Again, that doesn’t affect its current position, but it does affect its trajectory. Making the ball go faster forward increases height at the opposite side of its orbit, so if we push it with the right amount of force, we can make its orbit circular!

    Now you know enough to get a rocket to space! Well, kind of. You also need to know about fuel and the tyranny of the rocket equation, but that can wait until you play Kerbal Space Program or get a job at NASA

    • starman2112@sh.itjust.works
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      10 months ago

      Let’s imagine we’re in a rocket ship in a circular orbit, and we want to go back to earth. You might think you need to point towards the ground and turn your engine on, but remember how we got up here–we’re in orbit because we’re going sideways very fast. The most efficient way to come down is to point backward along our orbit and slow ourselves down, to lower the height at the opposite side.

      What happens if we do point straight downward? Well, we would start going downward, but because we aren’t pointing straight backward, we aren’t actually reducing our speed, only changing the direction of the orbit. It would take much more energy to come back to earth this way, and because we aren’t actually reducing our speed, it would be much more dangerous, because we would be entering the atmosphere faster than if we had pointed backwards instead.

      In a worst case scenario, we would run out of fuel before re-entering the atmosphere. This is very bad, because as we fall towards the earth, we start moving faster. Remember how moving faster at the lowest point in an orbit increases the height of the highest point? If we don’t hit the atmosphere, the top of our orbit will end up even higher than it was before!

    • Blue_Morpho@lemmy.world
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      10 months ago

      The Guide says there is an art to flying", said Ford, “or rather a knack. The knack lies in learning how to throw yourself at the ground and miss.”

      • Douglas Adams
  • Firestorm Druid@lemmy.zip
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    10 months ago

    Did you know that having a constantly open mouth as a child is really detrimental to the development and growth of your mouth’s palate, your overall posture, your nose, and many other parts of your facial and bodily structure?

    Physiologically speaking, your mouth should be closed most of the time. If it is, the crown/tip of your tongue should rest right on top if your alveoles, ie. just before your upper front teeth. This leads to your palate being formed and molded as a child into what you should know today. If for some reason you only rarely have your mouth closed as a child, this can lead to a deformed palate, making it more difficult to speak in the future, breathe etc. Furthermore, you are more likely to get sick since you’re not breathing through your nose where all of the bacteria you passively inhale through the air are filtered out by your tonsils. Additionally, your nose may be malformed by its irregular use as well since the air your breathe in and out helps form your nose too.

    Potential reasons for not breathing through your nose might be problems with your jaws (overbite/underbite) or teeth, inflamed tonsils that hinder your ability to breathe through your nose, a too short tongue frenulum that hinders the ability to properly reach your palate, and more.

    Happy breathing. :D

  • fakeman_pretendname@feddit.uk
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    10 months ago

    The Ooh Ooh song is Temptation by New Order

    The Woo Ooh-ee song is Elevation by U2

    The Woo-ooh, Eeh-Ooh-Ooh song is Woo Hoo by The 5.6.7.8s

    The Ooh-Aah Ooh-Hoo Ooh-Hoo song is Who are You by The Who

    The Woo Hoo song is Song 2 by Blur

    The Woop Woop song is Sound of Da Police by KRS-One

    Hope this helps.

      • Metans@lemmy.world
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        10 months ago

        The first one sounds like Down With The Sickness by Disturbed

        I think the second one is the theme from Doctor Who

        • fakeman_pretendname@feddit.uk
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          10 months ago

          To be fair the original knowledge was flawed.

          Temptation is more of a Ooh-e-Ooh Ooh-e-Ooh Ooh-oo-oo-ee-ooh Ooh-oo-oo-ee-ooh, so I can see the confusion.

          However, unless they’ve changed it in the last few years, I would have said Doctor Who is more

          Wee-Ooooh Whoo-Ooh-Oo-Oo (Daddle-a-da daddle-a-da daddle-a-da daddle-a-daddle) Whoo-oo-oo wh-oo wh-oo-oo. (Daddle-a-da daddle-a-da daddle-a-da daddle-a-daddle)

          [Edit] Apologies, I’ve just realised you were replying to a reply of a reply, I didn’t follow the little lines properly and got confused.

  • Ananace@lemmy.ananace.dev
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    10 months ago

    If you build a linked list in C, and put the pointer to the next entry as the first element in your struct, then you only need a single variable (and two comparisons) to do sorted insertion into the list.

    • Blue_Morpho@lemmy.world
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      10 months ago

      That’s too complicated for me to understand so here is my thing I know:

      When using example code from the Internet, it’s important to read the comments at the top of the file before going to far into adapting it and then wondering why it isn’t working.

    • Ook the Librarian@lemmy.world
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      10 months ago

      I got a good deal on a laptop and removed the hard drive with the preinstalled windows almost immediately. I say “almost” because I did actually set up a work space and installed software on in. It was a just-in-case system.

      My laptop has been running linux-only for a while. But my wife needs my lappy for a thing. And it’s a windows-only thing. So I remove my hard drive. Put in the pre-installed one I had sitting on a shelf. And it didn’t boot. I got a windows error screen saying I had better start rounding up boot recovery material. So fuck.

      Put my linux hard drive back in. BIOS can’t find a bootable drive. Fuck.

      I was able to fix the problem. I kinda hate to admit that it was kinda fun to fix. (If you haven’t chrooted, you haven’t lived.) But I’m just pissed off at that whole #!

  • Ethanol@pawb.social
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    10 months ago

    I know a fun fact:
    You know how a packet of 8 bits is called a byte? A packet of 4 bits, which is half a byte, is called a nibble!