Diference between Vrms & ac value of a signal

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SUMMARY

The discussion clarifies the difference between Vrms (Root Mean Square voltage) and AC voltage values. Vrms is a measurement that reflects the effective voltage of an AC signal, particularly for sinusoidal waves, and is typically measured using a multimeter or oscilloscope. The RMS value is directly related to the heating effect of the signal, as it represents the equivalent DC voltage that would produce the same heating in a resistive load. For sinusoidal signals, the RMS value can be calculated by multiplying the peak voltage by 0.707 (or \sqrt{2}/2).

PREREQUISITES
  • Understanding of AC signal characteristics
  • Familiarity with multimeters and oscilloscopes
  • Knowledge of basic electrical concepts, including voltage and current
  • Mathematical skills for calculating RMS values
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  • Research how to measure Vrms using a digital multimeter
  • Explore the mathematical derivation of RMS values for different waveforms
  • Learn about the heating effect of AC signals in resistive loads
  • Investigate the differences between RMS and average voltage measurements
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Electrical engineers, technicians, and students studying AC circuits and signal analysis will benefit from this discussion.

sphyics
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What is Vrms value. How can i measure it practically with whatever instruments (read voltmeter, oscilloscope). is it some mathematical stuff or we can measure it directly as voltage is measured.


so please tell me the difference between rms value and ac value of a signal, is rms value releated to some heating effect...
 
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For a sinusoidal wave, you can measure peak voltage, peak-to-peak voltage, average voltage over a half-cycle, or effective (http://en.wikipedia.org/wiki/Root_mean_square" ) voltage. RMS voltage of an ac source is usually what you will measure with your hand-held multimeter.
 
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You could also use your oscilloscope, read the peak voltage and multiply by 0.707 (or more specifically, by \sqrt {2}/2). If you take a look at this page it may clarify the meaning for you.
 
thanks dlgoff, Ouabache for the valuable informations.
 
Most likely this can only be answered by an "old timer". I am making measurements on an uA709 op amp (metal can). I would like to calculate the frequency rolloff curves (I can measure them). I assume the compensation is via the miller effect. To do the calculations I would need to know the gain of the transistors and the effective resistance seen at the compensation terminals, not including the values I put there. Anyone know those values?

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