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Why there are some electrical appliances use DC and some use AC ?
- mark (age 12)
The difference between these appliances is basically just how they work. DC is useful for appliances that run on a steady current itself. Just about all electronic devices use DC. For example, your TV plugs into an AC wall outlet, but the first thing that the circuitry in the TV does is convert this into DC, which is what the rest of the circuitry needs.
AC is useful for appliances that work based on the fact that the current is constantly changing. (When you have a current that is changing, it creates electromagnetic fields that can be useful.) I think the best way to understand this, though, is to understand what the difference between AC and DC really is - to find out, look here
(republished on 07/13/06)
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