An inductor is best defined as which of the following?

An inductor is best defined as which of the following?

• A. A coil of wire that opposes any change in current
• B. A device that stores electrical energy in a magnetic field
• C. A resistor designed to limit current
• D. A conductor used for grounding

Answer: (A)

An inductor’s defining trait is that it resists changes in current. When current tries to change, the inductor generates a voltage that opposes that change (back EMF). This behavior is captured by v = L di/dt, where L is the inductance. Because of this, a coil of wire designed to exhibit this property is an inductor. It also stores energy in its magnetic field as a consequence of that same behavior, but the primary description is this opposition to changing current. A resistor only limits current, and a grounding conductor is for safety/return paths, not an inductor.

An inductor’s defining trait is that it resists changes in current. When current tries to change, the inductor generates a voltage that opposes that change (back EMF). This behavior is captured by v = L di/dt, where L is the inductance. Because of this, a coil of wire designed to exhibit this property is an inductor. It also stores energy in its magnetic field as a consequence of that same behavior, but the primary description is this opposition to changing current. A resistor only limits current, and a grounding conductor is for safety/return paths, not an inductor.