You are constructing an air-core inductor using a coil of wire. What parameters determine its inductance?

The inductance of an air-core coil is strictly determined by its physical geometry and dimensions. The three primary geometric factors are the number of turns of wire, the diameter of the coil, and the length of the coil itself. Increasing the number of turns or the diameter of the coil increases the total inductance. Conversely, stretching the coil to increase its length (without adding more turns) spaces the wires further apart, which weakens the concentrated magnetic field and decreases the inductance. Other parameters listed in the distractors, such as the type of wire, coil orientation, or the operating frequency, do not fundamentally change the inherent inductance value of the component. The wire material affects resistance, while frequency relates to reactance, not base inductance.