• Warl0k3@lemmy.world
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    9 hours ago

    You can short the terminals on a car battery with your body with no issue (there’s a theory that that’s why you see it in movies so much - if anyone actually tries it the studio isn’t giving them an idea that actually works. Same with duct-tape gags and chloroform), but it might melt the hardware and set the floor on fire which would be fun! What they should really do is connect a HV source and charge up the pole. Won’t cause any lasting harm, but hopefully it’ll convince them they drove a screw through a live wire.

    • asbestos@lemmy.world
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      7 hours ago

      Who the hell told you you can short a car battery with your body? You absolutely can’t.

      • socsa@piefed.social
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        7 hours ago

        You definitely can. As in you can grab both terminals and not be injured.

        Source: am high level electrical engineer.

        • Fubarberry@sopuli.xyz
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          7 hours ago

          The way you worded it makes it sound like it’s very easy to short a battery with your body, not that attempting to short a battery will cause “no issue” because it won’t actually work.

          • Warl0k3@lemmy.world
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            7 hours ago

            I’m aware - I very intentionally spared everyone the lecture on the mechanics of how this works because it is, on the whole, very boring. However if we really wanted to get into the boring technical details nobody but us cares about then yes, you are indeed shorting the battery, it’s just for a ludicrously small amount of current. Ohms law (I = V/R) gives us that.

            • tomiant@piefed.social
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              5 hours ago

              Oooh, because we’re too dumb to understand the finer details of electrical engineering, is that it? IS THAT IT?

              Because yeah I am too dumb to understand even the coarser details of electrical engineering.

            • Fubarberry@sopuli.xyz
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              6 hours ago

              Thing is, you also called it “shorting” the battery. Usually a short is an unintended, unsustainable low resistance path.

              While your body may technically close the circuit, calling it a short makes it sound like an actual electricution risk. That combined with the unclear “no issue” usage made it pretty confusing, I thought you had no idea what you were talking about until I saw your reply.

              • Warl0k3@lemmy.world
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                6 hours ago

                It’s just the common parlance. I wouldn’t have done this were it a more technical setting, but this is a shitpost community - so I’ll just have to beg forgiveness for my imprecision. Fortunately, should anyone go to test this by fondling their car’s terminals, no harm will befall them due to my lack of strict accuracy in the description here (though they might get rebuffed by their car if it’s not in the mood).

                • sem@piefed.blahaj.zone
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                  5 hours ago

                  A short circuit is when you provide a path for electricity to travel directly from A to B.

                  You can’t do this by touching the battery terminals because your dry skin won’t transmit the electicity. You’re just touching battery terminals.

                  If you hold a AA battery in between your finger and thumb, you’re also not short circuiting it. You’re just holding it by its terminals.

                  But if you hold an unfolded paperclip to both sides, you are shorting it. The electricity can travel through the paperclip.

                  If you hold a nine volt battery against your dry palm, it’s not a short circuit. But if you hold it against your tongue, it is a short circuit because the electricity can travel through your (wet) tongue. You can feel the difference.

                  As far as I know, there is not a large population using “short circuit” the way you were (just touching a battery terminals).

                  • Warl0k3@lemmy.world
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                    4 hours ago

                    No, there is absolutely current flowing when you touch both terminals, it’s just an incredibly tiny amount. You can do the math yourself and see, it’s a basic application of Ohms law. The formula is (I=V/R). The reason you feel the tingles from a 9 volt you lick vs one you touch with your finger is that the resistance is much lower when licked, allowing more current to be produced - but the resistance is not infinite when you touch it with your finger, it’s just high enough that you do not notice the tingling from the small amount of current that results from a circuit with such high resistance (also it travels across the surface and on a much less sensitive part of your anatomy etc. etc.)