Calculating RMS Value for Unequal Peak Amplitudes

AI Thread Summary
To calculate the RMS value for a wave with unequal peak amplitudes, the standard formula of peak positive amplitude divided by root 2 does not apply directly. Instead, it is suggested to average the amplitudes, effectively shifting the reference point to equalize positive and negative amplitudes. The RMS voltage can be calculated using the formula √(V1² + V0²/2), where V1 represents the constant offset voltage and V0 is the sinusoidal amplitude. The discussion highlights the importance of understanding the relationship between the amplitudes to achieve an accurate RMS calculation. Clarifications and detailed calculations can be provided upon request.
lavster
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If I have a wave that looks pretty much sinusoidal but the peak positive amplitide is greater than the peak negative applitude how do I calcualte the rms vlaue - is it still the peak positive amplitude divided by root 2?
Thanks :)
 
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I would take an average of the amplitudes. but how large is the difference? If you take an average it would be equal to move the refrence point to where the amplitudes is equal for both the negative and the positive. and then it is a perfect sinusoid.
 
Interesting question!

Unless I've miscalculated, the rms voltage is given by \sqrt{V_1^2 + \frac{V_0^2}{2}} in which V1 is the constant offset voltage and V0 is the amplitude of the sinusoidal voltage.

Calculations can be revealed if requested!
 
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