Distribution of charge wrt static electricity

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
4 replies · 3K views
GRB 080319B
Messages
107
Reaction score
0
How is static electricity charge distributed over the human body if skin (1100 - 496,000 ohms) is a good insulator? For example, if one wears rubber-soled shoes and walks around on a rug, the shoes will obtain a negative charge. Then, if one touches a doorknob or some other metal object, a spark can result. My question is if charge is migrating from the shoes and being distributed throughout the body, or is the charge on the shoes creating an electric field that is inducing a negative charge in other parts of the body, such as the hands, which discharges to a grounded object? Is there a current or simply an induced charge?
 
Physics news on Phys.org
Hrmm. I think its a little bit of both effects, but I'm not sure. Remember that static electricity has a very high voltage, but very little current. I have had training on Electrostatic Discharge protection for electronic components, and it is possible for static electricity to damage an electronic component when you touch it, but not have enough current/voltage for you to even feel a shock. This is one way latent failurs happen in electronics. I'd say this is enough voltage to travel through your body, but little enough current to cause any harm.
 
Charge moves spontaneously from high potential to low potential. If the resistance is high, the rate is very slow.
 
If the sole of the shoe is perfectly insulating, it could charge the body only by induction. However the sole is very small compared to the body so you wouldn't get enough charge that way to feel a spark.
If you rub your shoes on a rug and get a spark the soles must be at least slightly conductive.
 
DrZoidberg said:
If the sole of the shoe is perfectly insulating, it could charge the body only by induction. However the sole is very small compared to the body so you wouldn't get enough charge that way to feel a spark.
If you rub your shoes on a rug and get a spark the soles must be at least slightly conductive.

Yes, shoes do have some conductivity. Just not a lot. I don't believe there is a perfect insulator.