DC through an inductor — what limits it?: In a DC circuit after transients, the current through an ideal inductor is limited by the total series resistance in the loop (source resistance plus any resistors). Decide whether this statement is correct.

Introduction / Context:Inductors behave differently during transients and in steady-state. In DC steady-state, an ideal inductor has zero voltage across it (di/dt = 0), acting as a short circuit. Therefore, the loop's resistances determine the final current value, a key point in power supply and relay driver design.

Given Data / Assumptions:

• DC excitation long after any switching event (steady-state).
• Inductor treated as ideal (no series resistance).
• The circuit includes finite series resistance: R_total.

Concept / Approach:In steady DC, di/dt = 0 implies v_L = L * 0 = 0. KVL then reduces the loop to the source voltage dropping entirely across resistive elements, so I_DC = V_source / R_total. The inductance value L influenced the transient ramp rate but not the final DC current (for an ideal inductor).

Step-by-Step Solution:

Verification / Alternative check:Measure current after a long time in a series RL step response; the final current equals V/R_total, independent of L (though the time constant tau = L/R_total set the rise time).

Why Other Options Are Wrong:

• Incorrect / iron core / depends solely on L / current cap at 1 A: Core or L affects dynamics and saturation, not the ideal DC final value; the final current is set by resistance.

Common Pitfalls:Confusing the time constant (which uses L) with the final steady-state current; overlooking small but present winding resistance in real inductors that should be included in R_total.

Final Answer:Correct