Calculate the reactance

*X*

_{C}. Choosing a capacitor

*C*and frequency

*f*is best.

Capacitive reactance (symbol

*X*

_{C}) is a measure of a capacitor's opposition to

AC (alternating current). Like resistance it is measured in ohms, but

reactance is more complex than resistance because its value depends on the

frequency (

*f*) of the electrical signal passing through the capacitor as well

as on the capacitance,

*C*.

Capacitive reactance,

*X*

_{C}= 1 / (2 × π ×

*f*×

*C*)

where:

*X*

_{C}= reactance in ohms (ohm),

*f*= frequency in hertz (Hz),

*C*= capacitance in farads (F)

The reactance

*X*

_{C}is large at low frequencies and small at high frequencies.

For steady DC which is zero frequency,

*X*

_{C}is infinite (total opposition),

hence the rule that capacitors pass AC but block DC.

For example a 1 µF capacitor has a reactance of 3.2 kΩ for a 50 Hz signal, but

when the frequency is higher at 10 kHz its reactance is only 16 Ω.

**Capacitance**

*C***, frequency**

*f***, and capacitive reactance**

*X*_{C}

Enter the values for capacitance and frequency, then press "calculate".

Sunder says

How to calculate the voltage drop across a capacitor. For example if I am connecting 135J in series to the phase what would be the voltage available on the other side

Swagatam says

There will no voltage drop when AC is passed through a capacitor, there will be drop in current.

If you connect 220V to a capacitor, the other side will also be 220V.

Nitesh says

i want to connect capacitor to the Mains in Series with the another circuitry ( series Impedance application )

Now which type ( polypropelene ,Metalised Polypropelen ,Film Foil type AC) & make like vishay ,deki ,ctr?

i will calculate reactance value as per my need.

Swagatam says

It can be of this type:

Nitesh says

Thanks for prompt reply.

sir may i choose interference suppression x2 type of vishay make ?

Swagatam says

Yes definitely you can use them!

Željko Kiš says

simply calculate-1 mikrofarad on 230VAC,50 Hz is about 70mA

Carl says

What is the meaning of c2 in your FM circuit? Please show me a photo of it.you said you can tune it with screw driver

freddy rafael sanchez sanchez says

gracias por la calculadora gracias por sus articulos le estoy siguiendo gracias por difundir conocimiemto util para nosotros le felicito por su loable gesto freddy sanchez managua nicaragua

Swagatam says

Thank you! Appreciate your response very much!!