Allan
Stunt Coordinator
- Joined
- Oct 1, 2000
- Messages
- 205
Can anyone exlain the difference between AC power and DC power?
thanks,
Allan
thanks,
Allan
Alternating Current has the voltage running as a sine wave of amplitude, where the quoted value is actually the average amplitude.
A little nitpick: The average value of a sine wave is actually zero. The quoted value you refer to is the RMS (Root Mean Square) value, which is the peak value divided by the square root of 2. Therefore the AC voltage from our outlets actually swings from -155V to +155V.
We use the RMS value because it is equal to the DC voltage that would deliver the same amount of power.
Recap: We actually get 155V AC at home. We call it 110V AC because we the power we see is the same as the one we would get from 110V DC.
About why we get AC at home instead of DC, I would think that AC power is much easier to generate in large quantities than DC since large generators always involve mechanical energy (oscillation) , as opposed to chemical energy. Also, it is very easy to get DC from AC. The other way is much harder
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Holadem
Also, it is very easy to get DC from AC. The other way is much harder
Well, it's not harder per say, but it's very wasting. I don't remember the hard numbers, but when I was out sailing we had to be very "aware" of when we ran the inverter for things like the microwave and such. Because for every 10amps of battery power that went in, only 5-6 came out (may have been a little higher or lower) in AC power. I'm sure for more real world applications they have more effecient units, but it's still not going to be as easy as going from AC to DC, it's also a lot more expensive.
Andrew