On Mar 22, 2005, at 12:25 PM, Gary Schafer wrote:
> If what you say was true then there would never be any power into our
> transmission lines.
>
> Average power is not zero simply because there is no negative power.
>
> There is only RMS voltage and RMS current. No RMS power.
My sis-in-law's electric water heater uses 240V-rms at c. 30A-rms. If
there is no RMS power, why does the water get hot?
>
> Peak voltage is 1.414 times RMS voltage. Those conversions don't work
> with power.
>
> 73
> Gary K4FMX
>
> TexasRF@aol.com wrote:
>> I lost track of who said what/when;
>> In a sine wave the average voltage is zero therefore average power
>> is zero.In an ac circuit with sine wave voltage, average current is
>> also zero. One could be led to think that average power is also
>> zero?
>> There is an RMS value related to peak value divided by square root
>> of 2; same as peak times .707.
>> There is an effective value related to equivalent d.c. value which is
>> also equal to the rms value.
>> See Radio Handbook Alternating Circuits, Impedance and Resonant
>> Circuits Chapter, pg 3-3 in the 23rd Edition.
>> Historically we have always referred to peak power as 1.414 times
>> rms power but not sure of the basis for this. Perhaps someone else
>> knows.
>> 73/k5gw
>> _______________________________________________
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>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>
>
Richard L. Measures, AG6K, 805.386.3734. www.somis.org
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