Power factor meaning — does pf = 1 indicate a purely reactive circuit and pf = 0 indicate a purely resistive circuit?

Introduction / Context:
Power factor is central in AC power engineering, expressing how effectively current is converted into useful work. Misinterpreting its extremes leads to wrong conclusions about load types and energy efficiency.

Given Data / Assumptions:

• Power factor pf is defined as cos(φ), where φ is the phase angle between voltage and current.
• pf ranges from 0 to 1 in magnitude for sinusoidal systems.
• Purely resistive, purely inductive, and purely capacitive loads are the canonical cases.

Concept / Approach:
Power factor equals the ratio of real power P to apparent power S: pf = P/S = cos(φ). A purely resistive circuit has φ = 0 degrees and pf = 1, because all current contributes to real power. A purely reactive circuit has φ = ±90 degrees and pf = 0, because all current is reactive with no net real power consumed over a cycle. Therefore, the claim in the question reverses these meanings and is incorrect.

Step-by-Step Solution:

Verification / Alternative check:
Observe the power triangle: horizontal leg is P, vertical leg is Q, and hypotenuse is S. When φ is zero, Q is zero and S equals P. When φ is ±90 degrees, P is zero and only Q remains, so S equals |Q| with pf equal to zero.

Why Other Options Are Wrong:

• Choosing “True” mixes up the interpretation of pf, leading to incorrect assessment of load behavior and wrong corrective actions in power factor management.

Common Pitfalls:
Assuming that a large current always means low pf. Low pf originates from phase shift and reactive power, not simply from current magnitude.

Final Answer:
False