🔋college physics i – introduction review

Inductive reactance

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Inductive reactance is the opposition to the change in current by an inductor in an AC circuit. It is measured in ohms and increases with both frequency and inductance.

5 Must Know Facts For Your Next Test

  1. Inductive reactance ($X_L$) is calculated using the formula $X_L = 2\pi f L$, where $f$ is the frequency and $L$ is the inductance.
  2. As frequency increases, inductive reactance also increases.
  3. Inductive reactance causes a phase shift where the current lags behind the voltage by 90 degrees.
  4. It only affects alternating current (AC) circuits, not direct current (DC) circuits.
  5. The unit of measurement for inductive reactance is ohms ($\Omega$).

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