Editing 2642: Meta-Alternating Current

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{{w|Direct current}} is a unidirectional flow of electrons from a power source to something being powered, through one or more conductors, before returning to the power source via one or more other conductors, thus completing the circuit. Batteries produce direct current.  It is commonly used in electronics applications, including computers. {{w|Alternating current}}, on the other hand, frequently reverses the direction of electron flow, and is commonly used for longer-distance transmission (such as from the power plant to an outlet).
 
{{w|Direct current}} is a unidirectional flow of electrons from a power source to something being powered, through one or more conductors, before returning to the power source via one or more other conductors, thus completing the circuit. Batteries produce direct current.  It is commonly used in electronics applications, including computers. {{w|Alternating current}}, on the other hand, frequently reverses the direction of electron flow, and is commonly used for longer-distance transmission (such as from the power plant to an outlet).
  
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This comic proposes a humorous ''Meta-Alternating Current'', which uses a series of adapters to "alternate" between DC and AC current along the length of a connector. This is absurd in part because typical {{w|power inverter}} efficiency is 90%, and maximum {{w|bridge rectifier}} efficiency is about 99% for 120 V,{{actual citation needed}} so an {{w|extension cord}} made in this manner would lose about 11% power (compounded<!-- ...need a better word for this, but it's very much related to compound interest. It wouldn't be 100% loss after nine steps, but ~91% loss, i.e. 0.90*0.99)^9 -->) per such pair. For the wire shown in the comic, with seven pairs, the efficiency would be 0.89<sup>7</sup>, which is 0.45, that is, 45%.
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This comic proposes a humorous ''Meta-Alternating Current'', which uses a series of adapters to "alternate" between DC and AC current along the length of a connector. This is absurd in part because typical {{w|power inverter}} efficiency is 90%, and maximum {{w|bridge rectifier}} efficiency is about 99% for 120 V,{{actual citation needed}} so an {{w|extension cord}} made in this manner would lose about 11% power (compounded<!-- ...need a better word for this, but it's very much related to compound interest. It wouldn't be 100% loss after nine steps, but ~91% loss, i.e. 0.90*0.99)^9 -->) per such pair.  
  
 
The title text bemoans that an inverter, which converts direct current to alternating current, does not work in the other direction, as a layman's interpretation of the word "inverter" might assume. Rather, a separate device, a {{w|rectifier}}, also pictured in the comic, must be used for this second conversion. (However, a similar circuit to an inverter may be used to rectify in a process called {{w|active rectification}}.)
 
The title text bemoans that an inverter, which converts direct current to alternating current, does not work in the other direction, as a layman's interpretation of the word "inverter" might assume. Rather, a separate device, a {{w|rectifier}}, also pictured in the comic, must be used for this second conversion. (However, a similar circuit to an inverter may be used to rectify in a process called {{w|active rectification}}.)

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