The DC-equivalent heating value of an AC waveform; Vrms=Vpeak/√2 for a sine.
V_rms=√(mean of v²). For a sine, V_rms=V_m/√2≈0.707V_m. It gives the equivalent DC heating effect. Square waves have V_rms=V_m; triangle V_m/√3. Use true-RMS meters for distorted waves.
10 V peak sine heats a resistor like 7.07 V DC.
RMS value is what sets the heating effect and power of AC, so it is the standard way to quote AC voltage and current.
The DC-equivalent heating value of an AC waveform; Vrms=Vpeak/√2 for a sine.
RMS value is what sets the heating effect and power of AC, so it is the standard way to quote AC voltage and current.
The average of a sine wave over a full cycle is zero, so RMS is used because it matches the heating effect of an equal DC value.
Many only read RMS for pure sine waves. True RMS meters are needed for distorted or nonsinusoidal waveforms.
Typical applications include reading the 230 V RMS mains voltage on a nameplate, calculating the power delivered to a heater from an AC supply and choosing a meter that reads true RMS for distorted waveforms.
Study "Sinusoidal AC" first (topic 37 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Same power in a resistor as DC. Crest factor=V_peak/V_rms. Form factor.
10 V peak sine heats a resistor like 7.07 V DC.
The next topic is "Phasors", which builds directly on this one.
It is classed as Intermediate in Electrical Engineering (topic 38 of 106). It is an intermediate topic. Work through the beginner topics in Electrical Engineering first.
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