Register to reply

Why does electrical current passing through the human body hurt?

by much noise
Tags: body, current, electrical, human, hurt, passing
Share this thread:
much noise
#1
Jul23-09, 05:10 PM
P: 2
What's the electrical current messing up that's causing pain?
Phys.Org News Partner Physics news on Phys.org
Physicists unlock nature of high-temperature superconductivity
Serial time-encoded amplified microscopy for ultrafast imaging based on multi-wavelength laser
Measuring the smallest magnets: Physicists measured magnetic interactions between single electrons
negitron
#2
Jul23-09, 05:13 PM
Sci Advisor
negitron's Avatar
P: 842
Nerves.
much noise
#3
Jul23-09, 05:38 PM
P: 2
Care to elaborate? Can't just be nerves, anyway, because I know that sometimes it fries you. And you can't die from a lot of input coming in your nerves. (Can you!?)

maverick_starstrider
#4
Jul23-09, 05:56 PM
maverick_starstrider's Avatar
P: 1,165
Why does electrical current passing through the human body hurt?

Because muscles work by maintaining a potential difference along the muscle which, when discharge, causes your muscles to contract. Therefore, when you get electrocuted the excess current messes up this whole system and your muscles convulse (contractt and extend) wildly. Which can be quite painful.
maverick_starstrider
#5
Jul23-09, 06:03 PM
maverick_starstrider's Avatar
P: 1,165
However, to really answer you question our body DOESN'T detect electric current. The reason is simply because we never evolved to (not much evolutionary advantage in the natural world, the only exposure to electric current would be when we got struck by lightning). The convulsion of the muscles only occurs at a certain current level. However, we conduct current across our skin all the time and don't notice. If you were to take an oscilloscope (or a volt/multi-meter) and grab each terminal with different hands you would find that you have a 60Hz (depending on what region you're in) current conduction across you right this second. It's coming from your electrical sockets and conducting through you (this current is small of course). But such small currents are harmless to us and we don't notice them.
mgb_phys
#6
Jul23-09, 06:07 PM
Sci Advisor
HW Helper
P: 8,954
Along with what maverick said, your muscles are controlled by electrical signals, your heart is a muscle. The big danger from AC electricity is that the 60Hz makes your heart try and beat 60 times per second which exceeds the manufacturers recommended specification by quite a large margin - which generally leads to a failure.
negitron
#7
Jul23-09, 06:08 PM
Sci Advisor
negitron's Avatar
P: 842
Quote Quote by much noise View Post
Care to elaborate? Can't just be nerves, anyway, because I know that sometimes it fries you. And you can't die from a lot of input coming in your nerves. (Can you!?)
Yes, you can. That's what happens when current goes through the brain. It also kills by interfering with the heart's electrochemical triggers, either stopping it completely or causing it to flutter uselessly (a condition called fibrillation).

But the part that hurts is the nerves being electrostimulated.
maverick_starstrider
#8
Jul23-09, 06:15 PM
maverick_starstrider's Avatar
P: 1,165
Quote Quote by mgb_phys View Post
which exceeds the manufacturers recommended specification by quite a large margin - which generally leads to a failure.
lmfao!
mgb_phys
#9
Jul23-09, 06:24 PM
Sci Advisor
HW Helper
P: 8,954
If I ever have to have surgery I want some those "warranty void if seal broken" and "no user serviceable parts inside" stickers
Born2bwire
#10
Jul23-09, 11:51 PM
Sci Advisor
PF Gold
Born2bwire's Avatar
P: 1,765
Quote Quote by mgb_phys View Post
Along with what maverick said, your muscles are controlled by electrical signals, your heart is a muscle. The big danger from AC electricity is that the 60Hz makes your heart try and beat 60 times per second which exceeds the manufacturers recommended specification by quite a large margin - which generally leads to a failure.
Cripes, don't get me started on the warranty program either.


Register to reply

Related Discussions
Human body and topology General Math 19
Why direct current which is passing through conductor does not have self-induction? General Physics 13
Can it hurt an engine's performance by having to big of a throttle body? Mechanical Engineering 10
Power of the Human Body Biology 3
Masterbation can hurt men's body ? Biology 9