Inductance L is defined as the coil's ability to oppose a change in current flow and is measured in henries. Which option describes inductance most accurately?

• A. The amount of current flowing through the coil
• B. The resistance of the coil to DC current
• C. The characteristic of a conductor that opposes a change in current flow
• D. The impedance of the circuit at DC

Answer: (C)

Inductance describes how a conductor resists changes in current by generating a voltage that opposes those changes, a relationship captured by V = L di/dt. That makes the best description the one that calls inductance the characteristic of a conductor that opposes a change in current flow. It’s a property tied to how energy is stored in the magnetic field around the coil (E = ½ L i^2) and it’s measured in henries. When current is steady, di/dt is zero, so the inductive opposition is not about a fixed amount of current or a DC resistance, but about how the current is changing. The other statements describe aspects that aren’t what inductance fundamentally is: the actual current value, resistance to DC, or DC impedance.