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Q & A: Polarity, cathodes and anodes.

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Most recent answer: 03/01/2010
Q:
There is a confusion over naming (defining) Anode and Cathode,specialy when charging ang discharging. What's the right way identifying them. Thanks
- Rajen (age 17)
Brisbane
A:
In the old days of electronic vacuum tubes that were used for rectifying, amplifying, etc,  there was no question.  You hooked the negative end of the battery to the cathode and the positive end of the battery to the anode.  The reason was that the cathode was heated to a high temperature and boiled off electrons.  In order to attract the electrons to the anode you had to supply the correct sign of an  electric field.  The means connecting the anode to the plus side of the battery.  This terminology has continued to be used in modern semiconductor components.

LeeH

(published on 03/01/2010)

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