by Francis Jock

Created on: April 20, 2008

Applied electronics is a term that requires a bit of definition before delving into the theoretical side of electronic theory. Generally, the term refers to the physical phenomena involved in electronic conduction or current flow. It also refers to various ways in which these phenomena and the properties of resistance, inductance, and capacitance interact to govern the characteristics, ratings, and limitations of electronic devices. The term is useful in describing the application of electronics theory to the various branches of electrical and electronic engineering. Electron theory, on the other hand, is limited to constructing a viable working model representing our understanding of how electronic conduction occurs based upon careful observation and experimentation.

Electronic conduction (current) is the result of the flow of electrons in a conductive material, such as a copper wire. Metals such as copper, lead, tin and aluminum are the most familiar conductors of electricity. There are two components required to produce electron flow: a source of electromotive energy creating a difference of electronic potential between two points, and a conductive path. A simple example of this is the lighting bolt. Incredibly powerful discharges of electricity strike the earth some 100 times each second, or 8 million times a day. (http://www.nssl.noaa.gov/primer/lightning/ltg_clima tology.html)

A lightning bolt is the result of a huge buildup of electromotive energy, or force between earth and clouds with strongly circulating winds and high concentrations of water vapor. The circulating water vapor in the form of rain, snow, or hail pellets accumulates a significant electro-static charge within the clouds vaporous structure. At some point, the difference of potential between the cloud and the earth becomes large enough to exceed the dielectric breakdown point of the atmosphere. The result is an exchange of energy between the earth and the clouds, which we see as a flash of lightning. An average bolt of lightning carries a negative electric current of 40 kiloamperes (kA) (although some bolts can be up to 120 kA), and transfers a charge of five coulombs and 500 MJ, or enough energy to power a 100 watt lightbulb for just under two months. (http://en.wikipedia.org/wiki/Lightning)

Electronic devices, with the exception of some high-powered radar devices, operate at far less voltage and current levels. Common electronic circuits with low current flow demand use low voltage 1.5 to

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