1 Answer
Impedance is a measure of how much a circuit resists the flow of alternating current (AC). It's similar to resistance in a direct current (DC) circuit, but it takes into account not only the resistance (the opposition to current flow) but also the effects of inductance and capacitance, which are important in AC circuits.
In simple terms:
- **Resistance** (measured in ohms) is the opposition to current flow in DC circuits.
- **Impedance** (also measured in ohms) is the opposition to current flow in AC circuits, which includes both resistance and the effects of inductance (coils or inductors) and capacitance (capacitors).
Impedance is a complex quantity, meaning it has both a **magnitude** (how much opposition) and a **phase** (how the current and voltage are related over time). It can be written as:
\[
Z = R + jX
\]
Where:
- \(Z\) is the impedance.
- \(R\) is the resistance (real part).
- \(X\) is the reactance, which includes the effects of inductance and capacitance (imaginary part).
- \(j\) is the imaginary unit (used to represent phase shift).
So, in AC circuits, impedance tells you how much the current is slowed down and by how much the voltage and current are out of sync (shifted in phase) due to the presence of inductors and capacitors.
In simple terms:
- **Resistance** (measured in ohms) is the opposition to current flow in DC circuits.
- **Impedance** (also measured in ohms) is the opposition to current flow in AC circuits, which includes both resistance and the effects of inductance (coils or inductors) and capacitance (capacitors).
Impedance is a complex quantity, meaning it has both a **magnitude** (how much opposition) and a **phase** (how the current and voltage are related over time). It can be written as:
\[
Z = R + jX
\]
Where:
- \(Z\) is the impedance.
- \(R\) is the resistance (real part).
- \(X\) is the reactance, which includes the effects of inductance and capacitance (imaginary part).
- \(j\) is the imaginary unit (used to represent phase shift).
So, in AC circuits, impedance tells you how much the current is slowed down and by how much the voltage and current are out of sync (shifted in phase) due to the presence of inductors and capacitors.