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AC voltages and currents are usually quoted as which kind of value?

AC is normally quoted as rms values.

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  1. Peak
  2. Rms (root mean square) ✔
  3. Peak to peak

Why: The rms value is a kind of average that gives the same heating as the equal DC value. That is why a 120 V outlet is not labeled with its higher peak.

Huh, didn't know that: Average power for a resistor equals Vrms times Irms.

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References

Answer: Rms (root mean square). The rms value is a kind of average that gives the same heating as the equal DC value. That is why a 120 V outlet is not labeled with its higher peak.

  1. OpenStax University Physics Vol. 2, 15.4 Power in an AC Circuit openstax.org/books/university-physics-volume-2/pages/15-4-power-in-an-ac-circuit
    Alternating voltages and currents are usually described in terms of their rms values.
    Checked 2026-10-10.

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