What is the difference between impedance and resistance

On the other hand, impedance is the combination of both resistance and reactance Inductance and Capacitance. Similarly, it is also a measure of obstruction to the current flow in AC circuits. The impedance is caused mostly in the magnetic and electric fields due to the collision of electrons inside the conductor.

The electrical resistance of an object is the measure of the obstruction to the current flow in a circuit. Moreover, resistance can be observed both in DC as well as AC circuits. When electrons collide with the ionic particles of the conductor, the conversion of the electrical energy into heat takes place, ultimately introducing an element to obstruct the flow of current through the conductor, and thereby the resistance arises.

Over and above, the resistance of a circuit is affected by the length, cross-sectional area of the conductor, temperature, and resistivity material of the conductor. The SI unit of resistance is Ohms and is represented by the letter R. The measure of the resistance is determined by dividing the voltage by that of the current in the circuit.

Two or more resistances are added arithmetically. We cannot add two or more impedances arithmetically. Tow or more impedances are added vectorially. The current through a resistance is always in phase with the voltage across it. There is a phase difference between the current through impedance and voltage across it.

The magnitude of phase difference depends on the presence of inductance and or capacitance in the impedance. No operator is required to represent resistance. It is just written as scalar. Resistance is simply a real value. If you like what you are reading, please consider buying me a coffee or 2 as a token of appreciation. I have completed master in Electrical Power System. This will help me to continue my services and pay the bills.

Dipali Chaudhari. Resistance is the term used to denote the opposition to the flow of current in a circuit or material. It depends on the resistivity and dimensions of the material. The resistance offered by a material to the flow of direct current and alternating current remains the same. It is denoted by the letter R. In terms of voltage V and current I , resistance can be calculated using the following formula:.

Impedance is the opposition to alternating current. It is a combination of resistance and reactance.