DC Electric Circuits
Very large capacitors (typically in excess of 1 Farad!) are often used in the DC power wiring of high-power audio amplifier systems installed in automobiles. The capacitors are connected in parallel with the amplifier’s DC power terminals, as close to the amplifier as possible, like this:
What is the purpose of having a capacitor connected in parallel with the amplifier’s power terminals? What benefit does this give to the audio system, overall?
A 470 μF capacitor is subjected to an applied voltage that changes at a rate of 200 volts per second. How much current will there be “through” this capacitor?
Explain why I placed quotation marks around the word “through” in the previous sentence. Why can’t this word be used in its fullest sense when describing electric current in a capacitor circuit?
Two 470 μF capacitors connected in series are subjected to a total applied voltage that changes at a rate of 200 volts per second. How much current will there be “through” these capacitors? Hint: the total voltage is divided evenly between the two capacitors.
Now suppose that two 470 μF capacitors connected in parallel are subjected to the same total applied voltage (changing at a rate of 200 volts per second). How much total current will there be “through” these capacitors?
Capacitors often have letter codes following the three-digit number codes. For example, here are some typical capacitor codes, complete with letters:
Determine the meaning of letters used on capacitor labels, what the respective numeric values are for all the available letters, and then finally what these four specific number/letter codes mean (shown above).