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In an AC circuit, the current through a capacitor does what compared with its voltage?

Capacitor current leads voltage by 90 degrees.

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  1. Lags it by a quarter cycle
  2. Stays exactly in step
  3. Leads it by a quarter cycle ✔

Why: A capacitor draws the most current when its voltage is changing fastest, which is before the voltage peak. Inductors do the opposite and make current lag.

Huh, didn't know that: A capacitor's opposition to AC, its reactance, drops as frequency rises.

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He married her because he just could not resistor. Ohm sweet Ohm.
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References

Answer: Leads it by a quarter cycle. A capacitor draws the most current when its voltage is changing fastest, which is before the voltage peak. Inductors do the opposite and make current lag.

  1. OpenStax University Physics Vol. 2, 15.2 Simple AC Circuits openstax.org/books/university-physics-volume-2/pages/15-2-simple-ac-circuits
    The current through a capacitor leads the voltage across a capacitor by π/2 rad, or a quarter of a cycle.
    Checked 2026-10-10.

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