juz_ad
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Hoping some can explain this to me…
To get RMS/quadratic mean of a particular data set I would use:
sqrt((a^2+b^2+c^2…)/number of values in the set) = RMS. e.g. for a data set of (3, 6, 9, 12) I would have sqrt((3^2+6^2+9^2+12^2)/4) = 8.216 (3 dp).
For an AC waveform though - let's assume a single cycle of a sine at 2.8V Peak, I have to use sqrt(((peak/2)^2)/2) = RMS e.g. sqrt(((2.8/2)^2)/2) = 0.989 (3 dp) which is approximately equal to 1V RMS.
Why is that? If the 'data set' of the AC waveform is only one measurement (2.8V Peak) - why do I need to divide it by 2 before squaring and then divide it by 2 as though there were 2 values in the data set?
Thanks!
To get RMS/quadratic mean of a particular data set I would use:
sqrt((a^2+b^2+c^2…)/number of values in the set) = RMS. e.g. for a data set of (3, 6, 9, 12) I would have sqrt((3^2+6^2+9^2+12^2)/4) = 8.216 (3 dp).
For an AC waveform though - let's assume a single cycle of a sine at 2.8V Peak, I have to use sqrt(((peak/2)^2)/2) = RMS e.g. sqrt(((2.8/2)^2)/2) = 0.989 (3 dp) which is approximately equal to 1V RMS.
Why is that? If the 'data set' of the AC waveform is only one measurement (2.8V Peak) - why do I need to divide it by 2 before squaring and then divide it by 2 as though there were 2 values in the data set?
Thanks!