交流电压表的平均值定义？

峰值:
The peak-to-peak value of an AC voltage is defined as the difference between its positive peak and its negative peak. Since the maximum value of sin(x) is +1 and the minimum value is −1, an AC voltage swings between + Vpeak and − Vpeak. The peak-to-peak voltage, usually written as Vpp or VP − P, is therefore Vpeak − ( − Vpeak) = 2Vpeak.

有效值（平方根均值）：
AC voltage is often expressed as a root mean square (RMS) value, written as Vrms = Vpeak/sqrt（2）= Vpeak/1.414。

要翻译吗？

平均值：
交流电在半周期内，通过电路中导体横截面的电量Q和其一直流电在同样时间内通过该电路中导体横截面的电量相等时，这个直流电的数值就称为该交流电在半周期内的平均值。

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