14 Difference Between Resistance and Impedance

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In an earlier tutorials, we have learned the two main differences like-

In this post, we are going to study what is difference between resistance and impedance.

Resistance vs Impedance in Tubular Form

01[Definition] What is Resistance & Impedance?The property of the substance that opposes the flow or limits the current in an electrical DC circuit is known as Resistance.The property of the substance that opposes the flow and limits the current in an electrical AC circuit is known as Impedance.
02Symbol of resistance & ImpedanceResistance is represented by the ‘R’.
Impedance is represented by the ‘Z’.
03Useful quantitiesResistance depends upon the conductor’s dimension, resistivity, temperature.Reactance depends upon the frequency of the alternating current.
04Useful elementIt consists of only resistive elements (R).It consists of resistance (R) and reactance (X).
05Current FunctionsResistance is applicable for DC circuit.
Impedance is applicable for AC circuit.
06Phase angle Resistance has the same phase. It means that phase angle does not occur in the resistive circuit. Impedance has a phase angle.
07Real & Complex numberIt has only real value.It has a complex (i.e. real and imaginary) value.
08Electric PowerDue to the resistance, active power is consumed in the electrical circuit.
Due to the impedance, active and reactive power are consumed in the electrical circuit.
09Effect of Frequency In an electrical circuit, resistance is constant due to the zero frequency of DC current.
In an electrical circuit, the impedance varies according to the frequency of the AC current.
10Effect of PowerAccording to this property, the electrical power is dissipated in the form of heat.
In this property, the electrical power is dissipated and stored.
11Mesuring InstrumentResistance is measured by the ohmmeter.Impedance is measured by the impedance analyzer.
12Useful function of resistance & impedanceIt is useful to find out how much a circuit resists the flow of DC current.
It is useful to find out how much a circuit resists the flow of AC current including the AC reactance and DC resistance.

13. Symbollc representation of Resistance and Impedance

  • Resistance (R) Symbol:
  • Impedance (Z) Symbol:
Impedance symbol

14. Formula of Resistance and Impedance

  • Resistance Formula
Resistance (R)  = (Voltage / Current)                        (Unit- Ohm)   

Check Online Tool for Calculating Resistance.

  • Impedance Formula
Impedance (Z) = [√(R2 + X2)] = [√R2 + (XL-XC)2]        (Unit- Ohm)   

Where, XL is inductive impedance and XC is capacitive impedance.

These are the 14 basic points of comparisons between resistance and impedance with the help of basic concepts, symbolic representation, and their formula.

The similarity in between the resistance and impedance is a unit. Both has same unit i.e. Ohm (Ω)

If you have any queries about the relation between the resistance and impedance, you can hit the comment below.

Other realted Comparison:

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