Definition check – What does inductance do? Statement: “Inductance is the property of an inductor that produces an opposition to any change in current.”

Introduction / Context:
Inductance is a basic electromagnetic property central to filters, energy storage, and transient behavior. This item checks the textbook definition that relates inductance to opposition against current change (not against current itself—that is resistance).

Given Data / Assumptions:

• Inductance L relates voltage and current by v = L * di/dt for ideal inductors.
• We consider both air-core and magnetic-core inductors.
• Circuits may be dc or ac; the statement concerns change in current.

Concept / Approach:

Because vL = L * di/dt, a nonzero voltage appears across an inductor only when current changes with time. This induced voltage resists the change (Lenz’s law). In dc steady state (di/dt = 0), an ideal inductor behaves as a short, indicating no opposition to constant current—only to its change. Hence the statement matches the formal definition and is true.

Step-by-Step Solution:

Verification / Alternative check:

Transient tests show exponential current rise i(t) = Ifinal*(1 − e^(−t/τ)) in RL circuits, evidence of inductive opposition to change characterized by time constant τ = L/R.

Why Other Options Are Wrong:

“False” contradicts the constitutive law. “True only for ac circuits” ignores dc transients. “True only with magnetic cores” is incorrect since air-core inductors also have inductance.

Common Pitfalls:

Confusing inductance with resistance or reactance; forgetting that opposition is to change (di/dt), not to the steady value of current.

Final Answer:

True.