Circuit phase angle — is it the angle between total current and the applied source voltage?

Introduction / Context:
The circuit phase angle summarizes how reactive a load is. It links directly to power factor and the relationship among apparent, real, and reactive power in AC systems.

Given Data / Assumptions:

• Single-frequency sinusoidal excitation.
• Definition of phase angle φ within a linear circuit.

Concept / Approach:
By standard convention, the circuit (or load) phase angle φ is the angle by which the current leads or lags the applied voltage. Positive φ typically indicates current leading (capacitive), negative φ indicates current lagging (inductive). Power factor is cos(φ).

Step-by-Step Solution:

Verification / Alternative check:
On an oscilloscope with Lissajous or dual-trace display, measure time shift between v(t) and i(t); convert to angle at the operating frequency to obtain φ, which is precisely the angle between current and voltage phasors.

Why Other Options Are Wrong:

• Answering “False” would contradict textbook definitions used in power engineering and circuit analysis.

Common Pitfalls:
Confusing the sign convention; always specify whether φ is defined as current relative to voltage or vice versa and maintain consistency when computing power factor.

Final Answer:
True