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Power Supplies

 A power supply unit is a source of either a Constant Current or Constant Voltage irrespective of the load resistance. Power sources can be classified as either varying or non-varying, i-e AC or DC. AC stands for Alternating Current whereas DC stands for Direct current. Graphically speaking, the Alternating currents are those that vary in some periodic fashion electrically and reverse polarity several times. The voltage which causes an Alternating Current is called AC voltage. The figure below shows the wave shape of an alternating power source.




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What is vector group of transformer?

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Battle of Thermoplyae 480 BC

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Eclipses

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