Compare resistance and reactance.
| Resistance | Reactance |
|---|---|
| It is a property of a material or component that opposes the flow of current through it. | It is a property of a material or component that opposes the change of voltage across it. |
| It is measured in ohms (Ω). | It is measured in ohms (Ω). |
| It is caused by frictional forces that slow down the movement of electrons through a material. | It is caused by the capacitance, inductance, or frequency of a circuit element. |
| It dissipates energy in the form of heat. | It stores and releases energy in the form of an electric or magnetic field. |
| It remains constant irrespective of the frequency of the input signal. | It varies with the frequency of the input signal. |
| It determines the amount of current that flows in a circuit for a given voltage. | It determines the phase relationship between the voltage and current in a circuit. |
| It is used to control the flow of current in a circuit. | It is used to control the phase of the current relative to the voltage in a circuit. |
| It can be represented as a purely real value in a complex impedance. | It can be represented as a purely imaginary value in a complex impedance. |