The impedance triangle is used to visualize which quantities together?

• A. Resistance and Reactances
• B. Only Resistance
• C. Voltage and Current
• D. Capacitance and Resistance

Answer: (A)

The main idea is that impedance in AC circuits is a complex quantity with a real part (resistance) and an imaginary part (reactance). The impedance triangle places resistance on the horizontal axis and reactance on the vertical axis, with the hypotenuse representing the total impedance. This visualization shows how much of the opposition to current comes from resistance versus reactive effects. The magnitude of impedance is Z = sqrt(R^2 + X^2), and the phase angle between voltage and current is phi = arctan(X/R). Since reactance can be inductive (positive) or capacitive (negative), the triangle helps you see both components together. It’s not just about resistance, nor about voltage/current alone, nor about capacitance and resistance, but about resistance and reactance combined to form impedance.