Calculate Capacitive Reactance

Capacitive Reactance Formula:

\[ X_c = \frac{1}{2\pi f C} \]

Capacitive Reactance (X_c):

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1. What is Capacitive Reactance?

Capacitive reactance (X_c) is the opposition that a capacitor offers to alternating current (AC). Unlike resistance, which remains constant, reactance varies with frequency.

2. How Does the Calculator Work?

The calculator uses the capacitive reactance formula:

\[ X_c = \frac{1}{2\pi f C} \]

Where:

\( X_c \) — Capacitive reactance in ohms (Ω)
\( f \) — Frequency in hertz (Hz)
\( C \) — Capacitance in farads (F)
\( \pi \) — Mathematical constant (~3.14159)

Explanation: The reactance decreases as either frequency or capacitance increases. This inverse relationship is fundamental to AC circuit analysis.

3. Importance of Capacitive Reactance

Details: Understanding capacitive reactance is essential for designing and analyzing AC circuits, filters, timing circuits, and power factor correction systems.

4. Using the Calculator

Tips: Enter frequency in hertz (Hz) and capacitance in farads (F). For microfarads (μF), multiply by 10^-6 (e.g., 10μF = 0.00001F).

5. Frequently Asked Questions (FAQ)

Q1: Why does reactance decrease with frequency?
A: At higher frequencies, the capacitor has less time to charge/discharge, effectively offering less opposition to current flow.

Q2: What happens at DC (0Hz)?
A: At DC, capacitive reactance becomes infinite, which is why capacitors block DC current.

Q3: How is reactance different from impedance?
A: Reactance is the imaginary part of impedance. Impedance combines resistance and reactance in complex form.

Q4: What are practical applications of capacitive reactance?
A: Used in filter circuits, coupling/decoupling networks, oscillator circuits, and power factor correction.

Q5: How does reactance affect phase in AC circuits?
A: In a purely capacitive circuit, current leads voltage by 90 degrees.