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Electricity / Electronics
http://www.electronicsinschools.comRA Moffatt
Key Stage III Electronics Modelling in Livewire, PCB Wizard & Control Studio
Electronics lies at the very heart of our technological society. In just one
hundred years we have become totally dependent upon it.
Electronics cannot be avoided in a modern world and therefore everyone
living and working within this 'electronic society' should have an
understanding of the underlying systems and processes that maintain our
way of life. GCSE Electronic Products is designed to encourage young
people to consider working in this dynamic sector of industry that needs
able young people who can develop, service and maintain the increasingly
complex electronic highways and the control systems that are the key
building blocks of a modern technological society. The course helps to
address what DfES, DTI and the engineering professions have shown to be
one of the largest areas of skill shortage in the UK.
Why study electronics?
Try to imagine a world without electronics. It affects almost all aspects of out lives.
Electronics is essential in:
• the manufacture and storage of our food
• the control of almost all our transport vehicles and systems that enable them to move
safely.
• modern communications
• caring for our health
• monitoring and controlling the environment including heating, lighting and security
systems
• the storage of information
• maintaining the world's financial systems
• our entertainment
Practically every modern Intel Pentium processor main board features a
temperature sensor developed at Delft University of Technology. The
sensor detects when the processor starts to become too hot, and
switches on a fan to cool it down. As soon as the temperature drops to
an acceptable level, the fan is switched off. The temperature sensor was
developed by Dr. Anton Baker, who in April 2000 was awarded his
doctorate for his research on this subject (see also Delft Outlook 97.1),
and subsequently put into production by Philips. Although the sensor
performs admirably, it is still not perfect. It contains a temperature error
that can be as much as a whole degree Celsius. Professors Dr. Paddy
French and Dr. Gerard Meijer formulated a research assignment to find
out what causes the error and it was Fredrik Creemer rose to the
challenge and unveiled the mystery: transistors are sensitive to stress!
Electrum
The Greek word electrum meant amber (fossilized pitch). When rubbed with
animal fur, amber gains a static electrical charge. Over the years, the word
electrum gradually came to refer to the electrical charge rather than to the
amber itself.
The Difference Between Electricity and Electronics
Obviously the words "electron", "electricity", and "electronics" are closely
related. For historical reasons, we divide the science and engineering of
electrons into two parts; electricity, and electronics. Electricity is the domain
of motors, light bulbs, generators, and other "large scale" items. Electronics
has come to mean the domain of vacuum tubes, transistors, integrated
circuits, and other "small scale" items. We're covering electricity theory and
practice here, because it is an important sub-set of electronics that can be
dealt with as a stand-alone topic.
Electron Orbits
In the 1920's we thought that individual electrons had individual orbits around the
nucleus of an atom. We have come to realize that orbits are not a very
meaningful concept for electrons. We now describe electrons as existing in a
"cloud" that surrounds the atomic nucleus. At any given instant, an electron has
some statistical likelihood of being somewhere in that cloud. That is about all that
we can say!
Electricity - Atoms and Molecules
To explain Electricity we need to look deeply inside of everyday objects
to consider their primary ingredients. (We'll keep this brief and simple so
as not to bore you.)
Atoms
As you probably know, everything in the world, whether solid, liquid, or
gas, is made up of atoms. Each atom contains some number of
electrons, protons, neutrons, and other sub-atomic stuff. The nucleus
(central region) of each atom contains the protons (positive charge) and
neutrons (no charge). Electrons (negative charge) live in a cloud around
the outside. Since electrons and protons are charged particles, each
atom prefers to have the same number of electrons as protons
Atoms
www.rapidelectronics.co.ukwww.maplin.co.uk
www.cpc.co.uk
www.tep.org.uk www.opitec.co.uk
http://www.tep.org.uk/Nottingham/viewWMV.html
How cool is this? An easy to assemble kit that makes a working steam engine
powered by compressed air. Slick and made from a smart material, having this on your
desk says ‘high powered’ in more ways than one...
http://www.tep.org.uk/Frames/_f_trweb.html
http://www.reprise.com
http://www.reprise.com/host/circuits/default.asp
http://www.elm.maine.edu/
http://www.webwasp.co.uk/tutorials/b09-atom/index.php