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Electrical Impedance Formula:
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Electrical impedance is the measure of opposition that a circuit presents to the flow of alternating current (AC). It extends the concept of resistance to AC circuits and includes both magnitude and phase information.
The calculator uses the impedance formula:
Where:
Explanation: The formula calculates the magnitude of impedance by combining the resistive and reactive components using the Pythagorean theorem.
Details: Impedance calculation is crucial for designing AC circuits, analyzing power systems, designing filters, and understanding the behavior of electronic components in alternating current applications.
Tips: Enter resistance and reactance values in ohms (Ω). Resistance must be non-negative, while reactance can be positive (inductive) or negative (capacitive).
Q1: What is the difference between impedance and resistance?
A: Resistance applies to DC circuits and represents pure opposition to current flow, while impedance applies to AC circuits and includes both resistance and reactance components.
Q2: What does positive and negative reactance indicate?
A: Positive reactance indicates inductive behavior, while negative reactance indicates capacitive behavior in the circuit.
Q3: When is impedance used instead of resistance?
A: Impedance is used in AC circuit analysis where capacitors and inductors create phase shifts between voltage and current, unlike pure resistive DC circuits.
Q4: What are typical impedance values in electronic circuits?
A: Impedance values vary widely depending on application - from milliohms in power systems to kilohms in audio circuits and megaohms in high-impedance measurement systems.
Q5: How does frequency affect impedance?
A: Impedance changes with frequency - inductive reactance increases with frequency, while capacitive reactance decreases with frequency.