Which is the Killer, Current or Voltage?




Sounds like many people insist that the current kills, not the voltage. Is that true? Watch the video and you shall know.




I hope the video is clear enough, if not, let me explain further.

What is electrical current? It is like any other current from many aspects, such as water current. The electrons flow in a wire, similar to water flowing in a pipe. Just that unlike the water that flows inside of a pipe, the electrons flow on the outer skin of the conductor.

How do you make water flow? You provide a difference in height and the water flows from top to bottom, but why? Because as you know, mass at a higher height has a higher potential energy than the one at a lower height. And so when the mass can move, it releases its extra energy by falling down to the lowest level it can go to, hence the water current.

The electrons don’t work the same way as they don’t really have much mass and there are much greater electrical reactions between electrons themselves as well as to the atoms cores exist. So if you hang a wire, the electrons won’t pure down like water does. There needs to be an electrical force or pressure, and that is the voltage.

Voltage in electronics is the same as pressure in mechanics. So in order for electrons to move, there must be some voltage difference between the two wire ends to push the electrons from one side to the other.



Like I said in the video, Voltage is equal to Current times Resistance (V = I x R). Since everything has some resistance, voltage is needed to create current. But if the resistance is zero, the voltage can be zero and there can still be current, I guess! So maybe in super conductors that work at temperatures close to absolute zero, you don’t really need voltage to create current? I doubt it as although there might not be resistance, there should be electrical attraction between particles with electrical charge that would dictate where the electrons will be and they won’t just start going. But don’t take my word for it and do your homework.

And in any case, they won’t just move, something has to make them move in the first place. So some energy is needed.

What I’m getting at is that energy is needed to create current. So current passing through body will kill of course, but there needs to be enough voltage to create enough current to interact with body organs like heart and kill. Similar to if I through a rock and hit someone in the head, the rock kills the guy, but I threw it. And you will never hold the rock accountable, which means really, the voltage is the main killer.

Hope that makes sense!



37 thoughts on “Which is the Killer, Current or Voltage?

  1. Right here is the perfect blog for everyone who wants to find out about this
    topic. You realize a whole lot its almost hard to argue with you
    (not that I personally would want to…HaHa). You definitely put a fresh spin on a topic that has been discussed
    for ages. Great stuff, just excellent!

    • This is just a crazed man with no proper training. Even the dumb lectrician knows that if there is in fact no resistance in the circuit and it is a purely capacitive or inductive circuit it in fact does not have electron flow it is impossible there’s no difference of potenti for which it to flow. If you fire back saying a transformer being a supporting fact you have to remember several power losses associated with them. Among these the voltage drop of wire feeding circuit, Eddy currents, hysteresis loss, magnetic flux loss, and the reluctance of the coil itself. In fact it is a mystery and a fact for now there is no current flow in a purely capacitive or Inductive circuit.

  2. Hi excellent website! Does running a blog like this require a massive
    amount work? I’ve very little knowledge of computer programming however
    I had been hoping to start my own blog in the near future.

    Anyhow, should you have any recommendations or tips for new blog owners please share.

    I know this is off subject however I just wanted to ask.

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  3. Hi! People! Please be careful about electrical safety! this subject might be trickier than you might think! I sincerely suggest you to do more research about it! There is a specific amount of current if pass through your body (also depends on where the path is, frequency etc … ) it will compromise functions of the heart. they call it Ventricular Fibrillation in medical terms. if somebody is caught in such an unfortunate situation and proper help is not available, death is immanent in matter of minutes! even if the source of current is removed! Ventricular Fibrillation, when it happens in hospital, where they can attempt to do emergency “Defibrillation” in the presence of doctors and nurses and required medical devices, still is very dangerous and might be fatal! I hope Mehdi do more research about this subject and post a follow-up video!

  4. Mehdi

    I know this is old topic, but I was wondering if you could elaborate on this further!

    I am looking at an electrohydrodynamic propulsion for some testing, and have a basic power source of a lipo battery (limited to continuous 15V 30A DC output).

    I use the Biefeld-Browning Effect

    The output force in Newtons is F = I * d / k
    I = current, d = distance between electrodes and k is the ion mobility coefficient.

    For air, k = 0.0002.
    Apparently the trick with distance is that 1kv/mm (1,000,000V/M) works best. so for a distance of 0.01m you need 10kv. So we will work with 1cm (0.01m distance) for now.

    Assuming we have a total of (30A * 15V) 450W to work with and we can transform perfectly as needed, we divide 450 by the 10,000V we have 0.045A.

    Note that since the distance D and current I are inversely related the force shouldn’t change based on distance? Sounds weird but whatever.

    So, as D increases, the voltage increases linearly [V = 1,000,000 * D] and the current decreases exponentially [I = 1 / (1,000,000 * D)]. Multiply by the input power source as needed.

    Is there some references to which distances are (or even could be) therefore safe? Since the voltage is 1kv even at one centimeter, I assume that small distances relying on low voltage (<10V) won't work. So is the trick to find a high enough distance where the current is too low to do anything? Or would any human part that bridges the gap just dump all that voltage into current and fry them?

  5. So what you are saying is that it is the wattage that kills (W=IV). Also, one other thing to add to this, the internal and external resistance of the body are very different. Once the flow of currant has overcome the initial external resistance of the body and created a pathway for itself, a much lower voltage is needed to maintain the flow. Modern Tasers deliver a much higher initial voltage then drop it down. Maybe you should test this.

  6. I love your videos man, but I have a problem with this one – not because it’s wrong, but because it perpetuates the misbelief that voltage is something that goes through you. I always hear things like, “Aw man I touched the wiring in my house and 110 volts went through me!”

    If someone dies from electric shock, the current is the murder weapon but the voltage is the murderer. Who’s to blame? In our justice system, we would accuse the voltage, however there is no question that the current is what actually does kill you. It’s just lacking the…intent?

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  8. Hi,

    I’ve been following some of you videos on youtube and 9gag.
    You are a great teacher/actor 🙂

    Keep up the good work

  9. If the electric chair were invented today would they design it differently? Since it was a westinghouse vs edison political thing. I understand AC is more deadly from your other videos, but politics aside if the electric chair was designed today to minimise pain and minimise time to kill, how would they design it today, like still AC? DC? the long jolt of 2400 volts for 45 seconds I think? What amperage? I am not trying to make my own chair, honest, I had always been fascinated by the electric chair as a rather crazy invention to kill somebody thinking it is more humane than hanging!

  10. Hi, Mehdi. I understood completely why the voltage is the cause of damage, but I dont get one thing…

    Why do you get 150A while having 20V and you still get 150A in 1V ?

    I don’t understand how that machine works, but from the little I know about this, I doesn’t seem possible to me.

    If I follow the Ohm Law, I get

    R = V/I being I = 150A and V = 20V, so I get a resistance of 0.133 Ohms.

    Assuming that the resistance is constant, replacing we have

    0.133Ohms = 1V/I —-> I = 7.5A

    Could you explain that to me? How can you get more current than 7.5A? Does it have something to do with an internal resistance of the machine?

    Thanks. Pablo.

    • Hi Pablo,

      That power supply is a current limited supply, tuned to 150A maximum. It means that as long as the output current is less than 150A, the output voltage is fixed at whatever it is set at, like 20V. But when the current tries to rise above 50A if we use a very small resistor, then the voltage starts to drop keeping the current at 150A. you are right that at 20V 150A the resistance would be 0.133ohm. But if I put a smaller resistance, like 10mOhm, then the supply limits the current to 150A, which means the voltage drops to 10m x 150 = 1.5V.

  11. hey mehdi,

    I really love your videos and the way you emphasize the importance of the safety precautions in such funny manner lol :D. mayb my question isnt referring to the video u have posted but I would like to know why the LED’s in this circuit remain intact when 58v (instead of 4V) appear across their terminals even though appropriate current passing through the circuit? I think it has some relevance to above video 🙂 http://s14.postimg.org/yxl7o8box/flt.png

    • Seems like there is no resistor series with LEDs to limit the current. Although the current draw is very small (100mA) anyways. So I think your model of LEDs is incorrect. Can you pick a model of a known part? A generic model may not work well in simulation.

      • yes, i wanted to use 5mm white leds but surprisingly there weren’t any white leds in the software 🙂 had to go with orange. and i think at least 17mA passing through every branch so i presume it shud light the leds. But i was expecting a closer value of 4v to appear across a branch but 58V?? o.0 this is how i calculated the reluctance of the cap : (230-4)/120*10^3 as usual but what happened to that 4V drop? Im not soo familiar working with ac circuits so could you please explain this? 🙂

        • I still think your LED model is wrong. For any voltage above 5 or 6V the current could shoot to 1A or above for single LEDs. Maybe instead of LEDs, put 5x regular diodes (1n4148 for example) in your model. Hopefully models for those standard LEDs work better. 58V is absolutely incorrect, especially for total ~100mA current you see in your simulation.

          • Thank you very much mehendi. Seems like there s smthing wrong in my multism 🙂

          • Without analyzing the numbers my guess is that because he is measuring RMS voltages and currents, the voltage value corresponds to the negative part of the wave, when the diodes are off and the voltage can rise without problems.
            So the simulation is correct.

  12. Mehdi,

    You are truly great. I love the mix of humor and science. Please continue the good work!

  13. Hey,
    could you pls explain certain things such as how electric water heaters work in high voltage 240 or more than that because it’s circuit will be simple but i donno how it works,
    how a computer SMPS distributes power supply to all i’s components, i would like to watch it as vid with your crazy burnout.
    i had destroyed one of my old laptop by giving 20v to all the IC and burnt it just to see how it burns like the way you did.
    you are rocking with these vids man they’re just awesome, i have seen all your vids and shared it with my friends,

  14. You’re funny, a little smart, a little careless, a little nuts, but funny!
    “Do it again dude!”, or, “Do something else smart, careless, nuts and funny dude!”

    David

  15. mehdi if you live in canada you should meet matthew santoto
    at least try !!
    he is also having his channel on you tube named matthew santoro.

  16. I just saw your video on voltage and I laughed my butox off thanks for the laughs but also be careful friend.

  17. I really like your videos and I’m doing a major in electronics and my project is an electronic harp. You can search for in in google I’m sure you’ll find a harp, now my question is: can you make a video showing how you build one?

      • well it should be finished in less than a month. I would finish it way earlier if I had more than 5hours in a week and there wasn’t “Passover” (jewish holiday) but during school we only work on our projects for 2 days in a week and only 5 hours during those days.

        anyway, I can’t wait for more of your videos.

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