capacitor impedance question ???

[eng_ahmed_osama]

why do we represent capacitor impedance by 1/jwcf , in practical what does this formula mean ??

And we get this formula ???

 

[carpenter]

Because impedance is complex number
https://en.wikipedia.org/wiki/Electrical_impedance

 

[eng_ahmed_osama]

Actually my question related to practical application , what is this means in practical life

 

[gs65]

@eng_ahmed_osoma: impedance refers to the resistive property of the capacitor. at low frequencies it is very high and for high frequencies it is low.by using this property only we are defining rc filters

 

[crutschow]

The impedance of a capacitor is inversely proportional to frequency as shown by the equation you referenced. We need that impedance value if we are to design the capacitor into electronic circuits to perform functions such as filtering, frequency shaping, and AC coupling of signals while blocking DC bias levels.

The formula can be derived from basic electrostatic derivations of capacitor operation. You can also measure the impedance versus frequency and see that it meets the derived equation.

 

[LvW]

The impedance of a capacitor is inversely proportional to frequency as shown by the equation you referenced.

...and we shouldn`t overlook the fact that the term "impedance" involves also a phase shift. This is an important property that is exploited in many circuits (example: integrating circuits).