The two solenoids A and B have the same diameter, the same length and contain only one layer of turns, closely adjacent to each other, since the thickness of the insulation is negligibly small. Solenoid A has a large number of turns of thin wire wound around it, and solenoid B has a smaller number of turns of thicker wire wound around it. Which solenoid has the highest inductance? Larger relaxation time constant?

Detailed solution. Format gif