Resistors are design to restrict the flow of electrons thru a current. Resistors are measured in ohm's which are represented by the Greek symbol omega. Resistor values are normally shown by using colored bands: black = 0, brown = 1, red = 2, orange = 3, yellow = 4,green = 5, blue = 6, violet = 7, gray = 8, white = 9. Most bands have 4 colors on them. The first color band represents the first digit, second color is the second digit, third color is how many zeros after (10 to the X power), and the fourth color is the tolerance of plus or minus where the resistance should approximately be. (

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History of Resistors

Resistors were first introduced between the 1950's and 1960's when integrated circuits were invented. This was the huge milestone for modern technology. An upgrade from undependable vacuum tubes to a more dependable product that still exists today. (Bennett, S.) American engineers, Jack Kilby(1923–2005) and Robert Noyce (1927–1990), first discovered within months of each other how to make a resistor. Within time American engineer Robert Noyce(1927–1990) improved the design and manufacturing of resistors. Finally, after years of production and improvement in Bell labs, Robert Noyce sold his first resistor in 1961 for his company. (Lee and Brenda Lerner)

Application of Resistors

As electronics became smaller,resistors had to be miniaturized too. Series or parallel, resistors are found in every circuit of today techonogly. Resistors are in many areas of scientific research: hearing aids, missile guiding systems, radios, etc. In the near future with nanotechonogly, resistors one day may be microscopic! (Lee and Brenda Lerner)
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  1. Ed. K. Lee Lerner and Brenda Wilmoth Lerner. Vol. 2. Detroit: Gale, 2009. p855-861.
  3. Source: Bennett, S. A History of Control Engineering: 1930–1955. Institution of Electrical Engineers, London, 1993, p. 42. Reproduced with the permission of the Institution of Electrical Engineers.]

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