Are there people that can pass huge amounts of current through their body and not feel it?
Well, It is obvious that the Mohan guy is absolutely fake. I hope nobody tries to find out if they are a super conductor watching Mohan, or they’ll be super dead!
Let me explain what effect different type of electricity would have on a human body:
- AC versus DC:
As I have shown in my previous article on pain of electricity a 50hz or 60Hz city power frequency hurts at double levels of a DC voltage. It is because of human body capacitance that allows more current through when AC is applied. I have measured this capacitance in another article here.
Like Dan mentioned, average human body resistance OVER SKIN is around 180 kOhm. Of course it is different between humans, skin conditions, humidity, different surfaces of body, etc…
The resistance significantly drops inside the body, to levels around 10kOhm and below. So for the same voltage, much more current flows if voltage is applies inside the body.
In average around over 100VDC on skin, most people start feeling electricity and around 300VDC is definitely dangerous and can be lethal depending on the path the current flows.
For AC, most people feel it for levels below 50VAC over skin and over 100VAC it is very dangerous.
The reason it is dangerous is that it can interfere with nerves of important organs like heart or brain and make them stop functioning.
- Skin Effect
Now AC pain level changes versus frequency as I showed in my other article (good thing I covered these before!). Some of this returns to how your nerves response to different frequencies. But a lot of it is skin effect.
Now skin effect is not relevant to human skin, but it is an electrical term meaning that at higher frequencies, electrons travel on a thinner layer on the surface of the conductor. This is because due to the electromagnetic fields generated inside a conductor, the electrons are pushed towards the surface of the conductor. The higher the frequency, the stronger this push is and results in this “skin” in which the electrons travel to become thinner. This has two meanings:
- The conductor is more resistive at higher frequencies because the area the current can pass through is smaller.
- In case of human body, the current at high frequency doesn’t penetrate deep enough to get to vital organs and kill the person.
You have seen this when I was touching my Tesla coil here. There was a lot of current through my body, so much that it would easily burn my skin, but I wouldn’t feel it besides burning my skin as it couldn’t get to my muscles and shake them.
So even at high frequency, electricity is still pretty dangerous as it can set your body on fire.
- High Voltage
Of course I’ve always said that it is the voltage that creates current that does the harm, which is the truth. Of course the current causes the damage but voltage is required to create current and time is needed to create more damage. Also the amount of current is not quite linear per voltage.
As the voltage rises, the current through the body rises based on the formula V = R x I assuming DC. You can replace R with body impedance for AC. BUT, as also you saw in the video, Mohan’s body resistance was increasing the longer he was holding it. And it was due to the fact that the tiny current the meter was putting out was changing skin surface properties where the probes touched. For example it was reacting with the body sweat, creating microscopic bubbles which would isolate the probe from body causing the resistance to increase. So when resistance increases, for the same voltage, current reduces.
Now if you increase the voltage too much, it wouldn’t need to go through body resistance, and rather it can break down the skin into a lower resistance, arc through and get to the low resistance internal tissues. This means the current suddenly spikes up and can be more damaging.
Such things happen when there is electrostatic discharge. Like when you touch your door knob and it zaps you. Those voltages are above 8kV and can easily arc over skin and go inside, so their currents are pretty large. But they are very fast too which means:
- Due to skin effect they won’t penetrate too deep
- Because they are very fast, they don’t have time to make damage
But if there is a voltage supply that can continuously provide high voltages (fixed voltage, don’t tell me the supply can be current limited, because in that case it won’t be fixed voltage), you will be easily cooked into Luke Skywalker’s aunt and uncle!
- 0-30V 0-10A Power Supply. I have this at work and home. It is small and reliable.
- Black Jack soldering station. Again have it at home and work. Very handy.
- And a whole bunch of other stuff you can get from their website