capacitive reactance
Quick Summary
Capacitive reactance is the opposition a circuit presents to alternating current due to the presence of capacitance. Capacitance involves the changing electric field between two conducting surfaces separated by an insulator.12
Unlike inductive reactance, which opposes changes in current, capacitive reactance opposes changes in voltage across the capacitor's plates. This opposition causes the alternating voltage to lag behind the alternating current.2
The formula for capacitive reactance ((X_C)) is the reciprocal of the product of 2π, the current's frequency ((f)), and the capacitance ((C)): (X_C = 1/(2\pi fC)). Capacitive reactance is measured in ohms.2
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