What is Reactance?

Reactance is the opposition that an inductor or a capacitor provides to alternating current (AC) due to its inductance or capacitance. Unlike resistance, which dissipates energy as heat, reactance stores energy temporarily in an electric or magnetic field and returns it to the circuit. It is measured in Ohms (Ω).

Inductive Reactance (X_L)

Inductive reactance is the opposition offered by an inductor to the flow of AC. It is directly proportional to the frequency of the AC signal and the inductance of the component. The formula for Inductive Reactance is:

X_L = 2πfL

Where 'f' is the frequency in Hertz and 'L' is the inductance in Henrys. As frequency increases, the inductive reactance also increases.

Capacitive Reactance (X_C)

Capacitive reactance is the opposition offered by a capacitor to the flow of AC. Unlike inductive reactance, it is inversely proportional to the frequency and the capacitance. The formula for Capacitive Reactance is:

X_C = 1 / (2πfC)

Where 'f' is frequency and 'C' is capacitance in Farads. In high-frequency circuits, capacitors offer very little reactance, effectively acting as a short circuit.

How to use the Reactance Calculator?

Using our online tool is simple and fast. Follow these steps:

1. Enter the frequency of your AC signal and select the unit (Hz, kHz, or MHz).
2. Enter the Capacitance value and select the appropriate unit (uF, nF, pF, or F).
3. Enter the Inductance value and select its unit (mH, uH, or H).
4. Click on the "Calculate Now" button to see the results in Ohms.

Frequently Asked Questions

Q: Why does DC have zero inductive reactance?
A: Because the frequency (f) of Direct Current (DC) is zero. Plugging 0 into the XL formula results in zero reactance.

Q: What happens to capacitive reactance at very high frequencies?
A: As frequency approaches infinity, capacitive reactance approaches zero, meaning the capacitor allows current to flow with almost no opposition.