AboutDan Fink Expertise Though my experience is mostly in the fields of electricity, magnetism, and physics, I have a broad science background. My career is in the field of alternative power sources -- solar, wind, water and battery power. But any questions about electricity, magnetism, energy conservation, power generation, electric motors, and even general physics are very welcome--especially from kids. They ask the best questions of all! I pride myself in answering science questions accurately, with ideas for SAFE, easy experiments that kids can perform by themselves--and that let them prove the answers to their own satisfaction. I think science should be fun, and available to everyone, regardless of age.
Experience I have volunteered in our local public schools for 5 years. I currently make presentations at our schools about electricity and magnetism, with a focus on solar, wind, water and other alternative power sources. I try to demonstrate at our schools how easy it is to make electricity, with simple devices using spinning magnets and coils of wire--powered by wind, water, bicycles, gerbils...etc. And of course solar panels! I am the webmaster of Otherpower.com, an alternative energy website. I have lived 10 miles from the nearest power pole for 11 years--I make all my own electricity from scratch with sun, wind and water.
Publications Otherpower.com
Wondermagnet.com
Co author of the book "Homebrew Wind Power" ISBN 978-0-9819201-0-8
My articles appear regularly in such magazines as Home Power and Back Home Education/Credentials BA Technical Journalism
Question Mr. Fink,
Hi...I am a student at Christopher Newport University. In my natural science class we have to do a 1 minute script/video project on a science concept of our choice and consult with a science expert on the information we are using in the video. My group chose to do our video on static electricity. If you can make sure all of these facts we are going to use in our video are correct I would really apperciate it. Thanks:)
-Static electricity is an electric charge built up on persons or objects through friction.
-Static electricity is electricity is electricity that does not flow in a current. It is generated by rubbing two nonmagnetic objects together.
-Usually substances that don't conduct current electricity (insulators) are good at holding static electricity.
-The electrons that are transferred in static electricity are stored on the surface of an object.
Answer Hi Sarah
Your information is pretty good, but there are some static electricity concepts that have very misleading names---'static' being the first among them. I highly recommend reading Bill Beatty's 'static electricity misconceptions' pages--you'll be amazed: http://amasci.com/emotor/stmiscon.html
This is where I'm getting most of the info in my reply below. Bill is very knowledgable and a very nice guy, too. He does give electrical science presentations on occasion, if he's ever in your area, go see him!
Much of this information comes as a surprise to even the best-educated adults. You will only have to change your presentation a little bit to get it exactly right, and you might astound some teachers and other students!
Here we go--
-Static electricity is an electric charge built up on persons or objects through friction.
It would be more accurate to say that it's an 'electric charge imbalance' that's built up. And friction is not required -- only close contact of two dissimilar materials, then separation. Friction can *help* build up the imbalance, by making more surface area come into contact and then separate.
-Static electricity is electricity is electricity that does not flow in a current. It is generated by rubbing two nonmagnetic objects together.
Current can and does flow with static electricity-- for example, current flows when you get a shock from the doorknob....and when this happens, 'static' is also flowing in you and in the doorknob--so you can make 'static' electricity flow within an object. So it's not really static at all--'static' is a very misleading term. I discussed the rubbing phenomenon earlier, friction is not needed. The magnetism of the objects does not enter into the equation here. So a better way to phrase your statement might be that --Static electricity is the name for an electrical charge imbalance that occurs when objects contact each other, and then separate. Atoms that hold their electrons more tightly can 'steal' electrons from less tightly held atoms on the other object.
-Usually substances that don't conduct current electricity (insulators) are good at holding static electricity.
Yes, that's correct...though as you've probably gathered already, static and current electricity are really the same thing. Insulators have very strong attraction between the atom and it's electrons and don't give them up easily. Conductors have much weaker attraction between the atoms and their electrons, so electric charge can flow freely....so in a conductor, 'static' is dissipated quickly and can't build up.
-The electrons that are transferred in static electricity are stored on the surface of an object.
That's a pretty good statement. The charges are near the surface because in an insulator they can't move easily.
BUT
The particles are not really 'stored,' because they all existed in the first place--equal amounts of positive and negative particles. All the static charge is, is when they are separated and no longer cancel each other out as they did when they were packed closely around the atom. But it's true that the negative ones (electrons) are most likely to move. SO it's better to say that the areas of greatest charge imbalance (both positive and negative) are near the surface of the object.
I hope I didn't throw too big a wrench in your presentation ;~) But just by changing you wording a bit you can get it absolutely correct.
