You are here:

Physics/Electricity and Static


Plastic combs can take electrons from our hair such that a plastic comb will develop a negative charge.  

So why doesn't plastic "insulation" around wire not store lots of static charge when we rub our hair on it?  Is the static charge absorbed by the metal wire inside the insulating plastic coating?  If so, does this interrupt the flow of electricity in wires?

Also, in regards to insulating plastic, does a negatively charged plastic comb not lose electrons to a neutral or positively charged plastic comb because they are the same non-conductive material?  Does the plastic comb hold a charge until a more conductive material can take the electrons?

So is it correct to say that -
1.  insulating materials can store charge but not conduct electricity?
2.  and that conductive materials store AND conduct electricity?


Yes, you're right that the charge stays in the metal itself.  The insulator doesn't have anything really to do with the electrical conductivity of the wire itself, that's determined by electron wavefunctions inside the metal (shared between atoms of metal).  You are also correct about the nature of the charged insulators, only a conductor will rob them of their charge.  Basically, you have answered your own questions, and your two final phrasings are basically correct in their statements.


All Answers

Answers by Expert:

Ask Experts


Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

©2017 All rights reserved.