Electricity & Magnetism
Inductive Reactance
Opposition to AC current flow by an inductor.
Variables
XLΩ
Inductive reactance
Opposition to AC by inductor
In SI units: kg·m²/(A²·s³)
Allowed values: greater than 0
ωrad/s
Angular frequency
ω = 2πf
In SI units: s⁻¹
Allowed values: greater than 0
LH
Inductance
Inductance
In SI units: kg·m²/(A²·s²)
Allowed values: greater than 0
Derivation
From V = L(dI/dt) for I = I₀sin(ωt), X_L = V₀/I₀ = ωL.
Your notes
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Check value
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- ω = 2 rad/s (Angular frequency)
- L = 3 H (Inductance)
Result: XL = 6 Ω
Other electricity & magnetism formulas with the same quantities
- Resonant Frequency (LC) (AC Circuits) shares Inductance
- Self-Inductance (Electromagnetic Induction) shares Inductance
- Inductor Energy (Electromagnetic Induction) shares Inductance
- RL Time Constant (Electromagnetic Induction) shares Inductance
Where this formula is listed
- Electricity & Magnetism formulas, under AC Circuits, alongside RMS Voltage/Current.
- In the electricity & magnetism list it comes after Capacitive Reactance and before Impedance (RLC Series).
- 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 Inductive Reactance formula?
Inductive Reactance is written X_L = ωL. Opposition to AC current flow by an inductor. It belongs to Electricity & Magnetism, under AC Circuits.
What are the units in X_L = ωL?
In SI units, X_L is inductive reactance, measured in kg·m²/(A²·s³); ω is angular frequency, measured in s⁻¹; L is inductance, measured in kg·m²/(A²·s²).
How is the Inductive Reactance formula derived?
From V = L(dI/dt) for I = I₀sin(ωt), X_L = V₀/I₀ = ωL. The result is X_L = ωL.