Question 164Electricity & Electronics - QMED

The correct answer is D) root-mean-square (RMS) voltage. Most AC voltmeters, whether analog or digital, are calibrated to measure the RMS value of an AC voltage. This is because the RMS value represents the effective or "heating" value of the AC voltage, which is the value that determines the power dissipated in a load. The RMS value is the square root of the average of the squares of the instantaneous voltage values over one complete cycle, and it is the value that is most useful for practical electrical measurements. The other options, such as peak-to-peak voltage (A) or peak voltage only (C), do not provide the same level of information about the effective power of the AC signal and are not the primary calibration for most voltmeters.