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06.10.2018: One Chapter of Nonfiction

Today's soundtrack is Christcentric: The Ephesians Project.

This evening, I'm reading chapter 14 of Larry Gonick's The Cartoon Guide to Physics, "Capacitors."

To make a capacitor, we separate two conductors by an insulator. To charge a capacitor, we transfer charge from one conductor to the other, usually with a battery. To do so, we create a switch that can be opened and closed that connects the battery to the capacitor. A closed switch transfers electricity from the battery to the capacitor. The capacitance of the capacitor tells us how much "charge the capacitor can store" (p. 124). Capacitance "is directly proportional to the area of the plates, and inversely proportional to the separation between them" (p. 124). Once the we charge a capacitor, it will remain charged for a period of time. We can quickly discharge a capacitor by connecting a capacitor's leads (the two wires sticking out of it). This is how large photography flashes work.

When a capacitor holds a charge, "positive and negative charges face each other and hold each other in place across the insulator" (p. 126). If we make a little hold on one side, the electric field created by the opposing charges will push an electron through, creating the "electron volt (eV)" (p. 127). With current technology, we can "accelerate charges to millions of electron volts [...] going close to the speed of light, and relativity theory must be used to describe them" (p. 127). The energy of the released electron will have the same number of electron volts as the charged plates have volts.


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