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Introduction of simple conduction, including the basic ideas and models of conductor.

Our initial studies will more or less be a review of topics in electricity that you may have seen before in physics. However,if experience is any guide, there is no great harm in going back over this material, for it seems that for many students, thewhole concept of just how electricity actually works is just a little hazy. Considering that you hope to be called anelectrical engineer one of these days, this might even be a good thing to know!

Most of the "laws" of how electricity behaves are really just mathematical representations of a number of empiricalobservations, based on some assumptions and guesses which were made in attempt to bring the "laws" into a coherent whole.Early investigators (Faraday, Gauss, Coulomb, Henry etc....all those guys) determined certain things about this strange"invisible" thing called electricity. In fact, the electron itself was only discovered a little over 100 years ago. Even beforethe electron itself was observed, people knew that there were two kinds of electric charge, which were called positive and negative . Like charges exhibit a repulsive force between them and opposite chargesattract one another. This force is proportional to the product of the absolute value of positive and negative charge, andvaries inversely with the square of the distance between them. Different charge carriers have different mass, some are verylight, and others are significantly heavier. Electrical charges can experience forces, and can move about. Since force timesdistance equals work, a whole system of energy ( potential as well as kinetic ) and energy loss had to be described. This has lead to our currentsystem of electrostatics and electrodynamics, which we will not review now but bring up along the way as things are needed.

Just to make sure everyone is on the same footing however, let's define a few quantities now, and then we will see how theyinteract with one another as we go along.

The total charge in some region is defined by the symbol Q and it has units of Coulombs. The fundamental unit of charge (that of an electron or a proton)is symbolized either by a little q or by e . Since we'll use e for other things, in this course we will try to stick with q . The charge of an electron , q , has a value of 1.6 -19 Coulombs.

Since charge can be distributed throughout a region with varyingconcentrations, we will also talk about the charge density , ρ ν , which has units of Coulombs cm 3 . (In this book, we will use a modified MKS system of units. In keeping with most workers in the solid-state devicefield, volume will usually be expressed as a cubic centimeter, rather than a cubic meter - a cubic meter of silicon is just fartoo much!) In most cases, the charge density is not uniform but is a function of where we are in space. Thus, when we have ρ ν distributed throughout some volume, V

Q ν V ρ ν
describes the total charge in that volume.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Introduction to physical electronics. OpenStax CNX. Sep 17, 2007 Download for free at http://cnx.org/content/col10114/1.4
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