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# Swagitance

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One note before I begin my wonderfully edumacative blog: Swagitance is like capacitance, except it measures swag in high-schoolers (units are still farads cuz that word's cool)

Anyways, capacitance. More specifically, circuits involving them. According to I-Town's resident electrical engineer (room# 3012), all those capacitor only circuits are practically wrong. Since V=IR, if there is no resistor, current is infinite and everythang would blow up (ie a calculator). Thus everything we had learned was a lie. which is semi-annoying... However when resistors are added, things get much more interesting, and realistic. When the circuit is first established, at time=0, the capacitor, as it is empty, acts like a wire, and current flows through it (I=max I) and Voltage (across capacitor)=0. However, as time goes on and the capacitor fills with charge, it limits the current flow across it, decreasing current but increasing voltage. Thus as time approaches infinity, current approaches zero while voltage approaches that of the voltage of the battery (asymptotic behavior), and the capacitor acts like a switch that has been opened creating a open circuit. As to why this happens, it's in the textbook. read it.

may have something to do with the allignment of molecules? not sure, as I need to actually read 25.4-.6 tonight... aka peace ya'll (in southern drawl)

## 1 Comment

Theoretically you are correct, you would have an infinite current and things would blow up. Practically, however, voltage sources have some internal resistance, as do wires, and in many cases, the capacitors themselves. But in general, you typically want a resistor somewhere in your circuit any time you have a capacitor involved to limit the current (errrr, damage) you may cause.

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