Basics Of Electricity - SIEMENS
Basics Of Electricity – SIEMENS (photo by

Elements of an Atom

All matter is composed of molecules which are made up of a combination of atoms. Atoms have a nucleus with electrons orbiting around it. The nucleus is composed of protons and neutrons (not shown). Most atoms have an equal number of electrons and protons.

Electrons have a negative charge (-). Protons have a positive charge (+). Neutrons are neutral. The negative charge of the electrons is balanced by the positive charge of the protons.

Electrons are bound in their orbit by the attraction of the protons. These are referred to as bound electrons.

Free Electrons

Electrons in the outer band can become free of their orbit by the application of some external force such as movement through a magnetic field, friction, or chemical action.

These are referred to as free electrons. A free electron leaves a void which can be filled by an electron forced out of orbit from another atom. As free electrons move from one atom to the next an electron flow is produced.

This is the basis of electricity.


An electric current is produced when free electrons move from one atom to the next. Materials that permit many electrons to move freely are called conductors. Copper, silver, aluminum, zinc, brass, and iron are considered good conductors.

Copper is the most common material used for conductors and is relatively inexpensive.


Materials that allow few free electrons are called insulators. Materials such as plastic, rubber, glass, mica, and ceramic are good insulators.

An electric cable is one example of how conductors and insulators are used. Electrons flow along a copper conductor to provide energy to an electric device such as a radio, lamp, or a motor. An insulator around the outside of the copper conductor is provided to keep electrons in the conductor.

Title:Basics of Electricity – SIEMENS
Size:2.5 MB
Download:Right here | Get Download Updates | Get Technical articles
SIEMENS - Basics of Electricity
SIEMENS – Basics of Electricity

Shape Up Your Knowledge //

Want to be a better electrical engineer? Subscribe to professional technical articles. Sharpen up your knowledge in field of electrical engineering now!

Subscribe Now

Page edited by E.C. (Google).


    Oct 09, 2015

    I visited this site first time and spent lot of time. I found it quite useful for engineers and learner.

  2. Tinashe Nyamazana
    Aug 25, 2015

    It will help us to undastand

  3. Ankur
    Aug 22, 2015

    Files are not downloading…..

  4. Paras Sharma
    Jul 22, 2015

    How to downlpad pdf files. I’m not able to download….please help

  5. Prof. Nazar M. Karyar
    May 19, 2014

    I will be glad to send me a sample design of power distribution network for a small city. The design may include all necessary steps to be followed in details. This is a critical need in Afghanistan. Only 6% of the main cities in Afghanistan had been electrified at this 21th century. We have quite lagging behind in modern technology that is a very bad image for Asia. As Afghanistan is the Heart of Asia , a cross-roads for all Asian countries let, we engineers as human being regardless of any ethnical differences or, no matter where we live must share the technological advances among our scientific forum and mutual advancements.
    Prof. Nazar M. Karyar Kabul-Afghanistan. E-mail:

  6. aijaz
    Jan 22, 2014

    I found this to be very help ful to the students of e e, to understand the basics of electricity.

  7. […] of another source charge, which has produced the electric field.We often express the strength of electric field as electric lines of forces. When we say electric lines of forces it is nothing but a vectorial way […]

  8. […] is essentially similar to the basic capacitor in the sense that it stores energy in an electric field. As such, it can quickly deliver and store energy because there is no chemical reaction involved. […]

  9. […] body will try to move in one direction, depending upon the polarity of the object.If an electron is placed between a negatively-charged body and a positively-charged body, the action due to the […]

Leave a Comment

Tell us what you're thinking... we care about your opinion!