# Simple conduction

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 $1.6E-19$ Coulombs.

Since charge can be distributed throughout a region with varyingconcentrations, we will also talk about the charge density , $\rho (\nu )$ , which has units of $\frac{\mathrm{Coulombs}}{\mathrm{cm}^{3}}$ . (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 $\rho (\nu )$ distributed throughout some volume, $V$

$Q=\int \rho (\nu )\,d \nu$
describes the total charge in that volume.

how can chip be made from sand
is this allso about nanoscale material
Almas
are nano particles real
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
no can't
Lohitha
where is the latest information on a no technology how can I find it
William
currently
William
where we get a research paper on Nano chemistry....?
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
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
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
revolt
da
Application of nanotechnology in medicine
has a lot of application modern world
Kamaluddeen
yes
narayan
what is variations in raman spectra for nanomaterials
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
what about nanotechnology for water purification
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
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?
what is a peer
What is meant by 'nano scale'?
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 ?
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
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