As an example, in the United States the standard value for the ac voltage supplied by a wall socket is 120 V; this is actually the rms voltage, so \(V_{\mathrm{rms}} =\) 120 V. The voltage amplitude, or peak voltage, is larger by a factor of \(\sqrt{2}\), so \(V_0 = V_{\mathrm{rms}}\sqrt{2} = (120\ \mathrm{V})\ \sqrt{2} = 170\ \mathrm{V}\).
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