Rms voltage

Definition

RMS Voltage (Root Mean Square Voltage) is the effective value of an alternating current (AC) voltage, which represents the equivalent direct current (DC) voltage that would deliver the same power to a load. It is calculated as $V_{rms} = V_{peak} / \sqrt{2}$ for sinusoidal waveforms.

5 Must Know Facts For Your Next Test

1. RMS voltage is used to calculate power in AC circuits because it gives the equivalent DC value.
2. For a sinusoidal AC waveform, RMS voltage is $V_{peak} / \sqrt{2}$.
3. RMS values are crucial in comparing AC and DC systems because they standardize varying waveforms.
4. $V_{rms}$ can be derived from integrating the square of the instantaneous voltage over one period.
5. $V_{rms}$ provides a meaningful measure of an AC signal’s ability to do work or transfer energy.

Review Questions

• How is RMS voltage related to peak voltage in a sinusoidal waveform?
• Why is RMS voltage important for calculating power in AC circuits?
• What is the formula for calculating RMS voltage from peak voltage?

Related terms

Peak Voltage: The maximum instantaneous value of an alternating current or voltage waveform.

Alternating Current (AC): An electric current that periodically reverses direction.

Direct Current (DC): An electric current flowing in one direction only, with constant magnitude.