Electromagnetism

Historical Background and Contemporary Public Interest in Electromagnetism

The traditional conception of the physical world was that it consisted of four elements, which were earth, air, fire and water. Similarly, modern physics also characterizes the physical world within the context of four forces, which are gravity, electromagnetism, and both strong and the weak nuclear forces. Contemporary physics holds that the elements are not primary, but are themselves composed from particles, such as protons and electrons, and that, in turn, these particles are composed of sim

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he long and strong approach may be termed the wide and weak approach, wherein noise, as opposed to being neutralized by with electrical power, is joined with electrical power--"not talking louder but talking softer in more elaborate codes using more bandwidth. For example, in transmitting 40 megabits per second--the requirement for truly high-resolution images and sounds--Shannon showed some 45 years ago that using more bandwidth can lower the needed signal-to-noise ratio from a level of one million to one to a ratio of 30.6 to one. This huge gain comes merely from increasing the bandwidth of the signal from two megahertz (millions of cycles per second) to eight megahertz. That means a 33,000-fold increase in communications efficiency in exchange for just a fourfold increase in bandwidth." The resulting increase in efficiency limits the need to use electrical power to overcome noise. More communications power comes from less electrical power. Shannon's theories and concepts provides the framework for the development of low-powered wireless communications. "This vision of wide and weak is at the heart of the most promising technologies of today, from the advanced digital teleputer sets of American HDTV to ubiquitous mobil
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Some common words found in the essay are:
PCNs Compensating, Bell Labs, Stephen Hawking, TDMA CDMA, Claude Shannon, Cray YMP, Termed Gaussian, James Maxwell, Cellular Vision, Thomas Freeberg, contemporary period, wide weak, subject evaluation, wireless communications, contemporary public, 28 gigahertz, physical world, 18 gigahertz, electrical power, times bandwidth, electromagnetic radio wave, power overcome noise, contemporary professional field, conference antennas propagation, contemporary public electromagnetism,
Approximate Word count = 3070
Approximate Pages = 12 (250 words per page)

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