Electricity & Magnetism
RMS Voltage/Current
RMS (root mean square) value of sinusoidal AC voltage or current.
Variables
VrmsV
RMS voltage
Root mean square voltage
In SI units: kg·m²/(A·s³)
VpeakV
Peak voltage
Maximum voltage
In SI units: kg·m²/(A·s³)
Derivation
V_rms = √(⟨V²⟩) = V_peak/√2 for sinusoidal waveform.
Your notes
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Check value
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- Vpeak = 2 V (Peak voltage)
Result: Vrms = 1.4142136 V
Where this formula is listed
- Electricity & Magnetism formulas, under AC Circuits, alongside Capacitive Reactance, Inductive Reactance and Resonant Frequency (LC).
- In the electricity & magnetism list it comes after Transformer Equation and before Capacitive Reactance.
- Electricity & Magnetism formula sheet, one of 48 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the RMS Voltage/Current formula?
RMS Voltage/Current is written V_rms = V_peak/√(2). RMS (root mean square) value of sinusoidal AC voltage or current. It belongs to Electricity & Magnetism, under AC Circuits.
What are the units in V_rms = V_peak/√(2)?
In SI units, V_r ms is rms voltage, measured in kg·m²/(A·s³); V_p eak is peak voltage, measured in kg·m²/(A·s³).
How is the RMS Voltage/Current formula derived?
V_rms = √(⟨V²⟩) = V_peak/√2 for sinusoidal waveform. The result is V_rms = V_peak/√(2).