This tool calculates the average voltage level of a sine wave over the interval π radians.
Enter the peak voltage (Vpeak) below to find the average level (Vavg)
Formula
Vavg = 0.637*Vpeak
Note that the average value of a sine wave over 2π radians or one complete cycle is 0 (zero).
Background
The average value of an AC voltage or current is the mathematical mean of all instantaneous values of voltage or current over the specified interval. In the case of a sine wave that is symmetric about the x-axis, the average value is zero.
Average voltage should not be confused with the root-mean-square voltage. Although they are related. This calculator uses the average voltage to compute the RMS voltage. The picture below shows the differences between average, RMS and peak voltage.
The average value depends on the interval over which the sine wave is averaged. The plot below shows the average over half a period.
RMS vs Average vs Peak Voltage
In a circuit, the values of AC voltage and current can be measured and expressed in different ways.
One common way is to represent them as peak values, which refers to the maximum magnitude achieved by the voltage or current in a given cycle.
Another way to express these values is through average values, which is the arithmetic mean over a complete cycle. Average voltage is used in the case of rectifiers as shown in the video below
However, the most commonly used representation is the RMS value, which stands for root mean square. The RMS value can be computed from a sequence of voltage measurements over time using this calculator.
The RMS value is a measure of the effective value of the AC voltage or current, equivalent to the DC value that would produce the same amount of power in a resistive circuit. It takes into account the square of the instantaneous values of the voltage or current over the entire wave cycle, and then calculates the square root of the average of these values. This is particularly important when dealing with AC sine wave signals, as most AC voltages and currents in practical circuits have sine-like characteristics.
When analyzing and designing AC circuits to understand and appropriately utilize peak values, average values, and RMS values.