**Impedance (Z)** is similar to **Resistance (R)** . Impedance and Resistance both oppose the current in circuit. Both are almost the same thing , But **resistance related to** **DC Circuit**. Resistance oppose the steady electric current in DC circuit. **Resistance** **remains same** (constant) at any different frequency range.

**Impedance is related with AC circuit**. Impedance **vary** accordting to changing the frequency, this is not constant at different frequency range. Impedance also includes reactance (Inductive and capacitive property of the circuit).

**Reactance- **Reactance is the Resistance produced to AC Currents by Inductors and Capacitors only. This is a measure of the type of opposition to AC electricity due to capacitance or inductance.

The **impedance** is denoted by **Z **and unit of it is **Ohm (Ω). **

If the level of ohm is higher then level impedance is also higher.

**Impedance = Resistance + Reactance (Either inductive or Capacitive or both)**

In DC circuit, **Impedance** is effective Resistance of the circuit.

** Z= R**

In AC circuits, it possesses both magnitude and phase, unlike resistance, which has only magnitude.

In the case of capacitor, When the frequency increased then the resistance (Impedance ) of capacitor decreases. In Inductor this is just opposite, When we increase the frequency range then Impedance increase in inductor.

**Impedance **** **

**Impedance is defined as combination of resistance and reactance.**

As we cannot assume any circuit with DC Current without Resistance , We cannot assume a circuit with AC current without Impedance.

Resistive Power- Energy burns by resistive power to Heat goes through that system ,

In Reactive Power- the energy goes to Antennas, Speaker, transmission line, cable etc represents how much energy to be stored and propagates. Not burn to heat ie Impedance.

**Resistance** ** **If there is Only

** • Reactance** ** **

__In Reactance There are 2 cases__

**(1) **If **inductor** in connected then in this case **reactance** is called **inductive** **reactance**,

and its value in scalar form X_{L} = ѡL, and in vector form X_{L}=JѡL Where ѡ=2Πf. Here If frequency is increased then the value of wL is also increased.

**(2)** If **Capacitor** is connected then the Reactance is called **Capacitive Reactance** and it is denoted by (scalar form) Xc =** **

In vector form ** ** Where

**♦ Impedance – ****If Any circuit consist Resistance –Inductor. Or Resistance – Capacitor, Or Resistance-inductor-Capacitor. Then the value of v/I is called Impedance.**

It is denoted by

**If Resistor(R) and Inductor(L)****connected –****The value of Impedance (scaler form)**

**In vector form Z= R+jωL **

**If Resistor (R) and Capacitor(C)****connected – Then**

**Impedance **** **

**And In vector form impedance **

**If Resistor (R) , Inductor (L) capacitor (C) Connected****– Then**

**Impedance **** **

**In vector form **** **

**Phasor Diagram of Impedance**

__Unit__

**Impedance****– Ω****Reactance****– Ω****Resistance****– Ω**

** Download **

**Also Read What is NOT Gate Logic **

Tags :

Thank you for this post. Its very inspiring.

very cool post, i actually enjoyed this web site, carry on it

Much interested have learnt alot from you

Carry on

It’s in reality a nice and useful piece of info. I’m glad that you just shared this useful info with us. Please stay us informed like this. Thanks for sharing.