We don't really feel a voltage , we feel a current not "amperage". The problem is that you generally have no idea about the skin resistance. Dry skin can have up to k or more, but there is no lower limit.
If you stick sharp probes straight through your skin, you'll get an almost perfect conductivity. Remember that we actually feel a current , and the current is related to the voltage and resistivity.
It doesn't take a high current for the human body to register it, and instead of reading through Wikipedia for you, I simply decided to test it. The part of my body with the least resistance is my tongue.
I hooked a voltage source up to my tongue and I could easily detect 1 volt. Less than that, maybe, but I would have to have someone help me with a blind test.
When trying the same probes on my slightly moist fingers, I could detect a voltage of around volt. I suspect that you confuse earth , ground , and negative. A circuit must be closed to flow. A battery is not a bucket of water that you can pour electrons from, even though a lot of teachers and texts out there apparently wants you to believe that. There must be a path of low resistance between the positive terminal of a battery and the negative terminal on the same battery for any current to flow from that battery.
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Once you're part of a circuit, current flows through you. And it doesn't take much current to do serious damage — from taking control of muscles to burning flesh and making hearts stop altogether. Mary Shelley knew a lot about writing bestsellers, but not much about the effect of electricity on the human body. Our bodies can detect currents as small as 1 milliampere 1 mA.
An electric socket can provide a current ten thousand times that size 10 A. The tiny 1 mA current stimulates our pain receptors, so we actually 'feel' it as a tingling sensation. We can handle currents up to 5 mA without any physical damage — the tingles just get stronger. But at currents greater than that, things start getting out of control, causing anything from burns and muscle paralysis to respiratory and heart failure.
Whenever electric currents flow through any material they produce heat, because the charges electrons or ions bump into atoms of the material they're flowing through. The heat from electric shocks can cause burns on the skin where the current enters and leaves the body, and in the tissues they pass through. A current flowing through your body obeys the same rule that a current in a wire does: follow the path of least resistance. And the part of our body with least resistance to electric current ie that its easiest for current to flow through is nerves.
Muscles are next, and then blood vessels. A current of mA is strong enough to override electrical signals from your nerves. Our nerves don't just send signals to and from the brain, they also control our muscles. By 30 mA any muscles controlled by the affected nerves are no longer under your control — the current causes the muscles to contract, and your arm or leg freezes. If your hand is holding the source of the current, you literally can't let go until the power is shut off.
And that brings extra problems. If your skin is in contact with the source of the current, it gets hotter and burns. Skin is much harder for a current to flow through than nerves or muscles. But once the skin has burned away, there's nothing stopping a much higher current flowing into your flesh.
And higher currents mean more damage. Electric currents don't just affect arm and leg muscles. If a current passes across your chest it can wreak havoc with two other critical muscles: the diaphragm, which controls our breathing, and the heart. We breathe because our diaphragm is attached to our lungs, so as it contracts and relaxes it causes the lungs to stretch and contract, forcing air in and out. This was the beginning of learning how to control these charges. Even today there are some engineers that believe static is an overblown issue.
Devices have various levels of sensitivity. It is reprinted here because it is important information when you determine the level of your ESD program. Voltage Range. Static Electricity Lightning is probably the most recognizable effect of static electricity.
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