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Joined 1 year ago
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Cake day: June 13th, 2024

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  • I think we all know where this is going.

    1. The Brainchip is trendy in Silicon Valley but doesn’t do much yet. The company says cyber-superintelligence will be available in a year, tops. Investors are pouring billions into it. Everyone says you need to hop on the trend now or you’ll be obsolete in six months.
    2. It’s been two years. The Brainchip still struggles to control a mouse or search Google. Everyone’s lost interest in building apps for it. Many users are reporting severe migraines, but the company says there’s nothing to worry about.
    3. The Brainchip pipes three unskippable ads directly to your optic nerve every time you go to the bathroom. Notifications ping your brain all day long. You can get it removed if you’ve got $80k to burn, but there’s a high risk of postoperative stroke.

    Yeah, no, I’m not putting anything in my brain that isn’t open-source from end to end. And even then probably nah.


  • isaacd@lemmy.worldtoxkcd@lemmy.worldxkcd #3090: Sail Physics
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    12 days ago

    Yes, it’s possible (and common) for a boat to sail against the wind by the power of its sail alone. Sailors have known this for hundreds of years but if it sounds impossible, no worries, I thought so too at first.

    Here’s how it works, simplified so I can get in trouble with pedants:

    The boat, first of all, has a keel (the blade-like bottom of the hull) which “locks” it into movement along a single axis: forward and backward. The wind is not going to blow the boat sideways, at least not very effectively.

    Second, sails are curved, not flat, and can rotate (when seen from above). The force created when the wind deflects off the sail matches the curve of the sail, more or less.

    So if the wind is blowing directly south ⬇️ and you want to travel north ⬆️ you angle the boat northeast ↗️ so it can only move northeast or southwest. Then you point the sail east ➡️ so the wind gets deflected west ↩️. Newton’s third law does the rest. When the wind hits, the boat will move northeast ↗️ because the keel prevents it from going straight east.

    Then after a while you turn the boat (“tack”) northwest ↖️, point the sail west ⬅️, and continue.