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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

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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
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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