self-inductance
Quick Summary
Self-inductance is a property of a conductor, often in the shape of a coil, that measures the electromotive force (voltage) induced in it by a changing electric current. This phenomenon occurs when a varying magnetic field, produced by a changing current within the conductor itself, induces a voltage in that same conductor.12
This induced voltage opposes the change in current that created it, acting like electromagnetic inertia. For example, when a current starts flowing, self-inductance resists its increase. Conversely, when a circuit is broken, the collapsing magnetic field tries to maintain the current, potentially causing a spark.1
The amount of self-inductance depends on the conductor's size, shape, coil turns, and surrounding materials. A coil with an iron core has higher inductance than one with an air core. The unit of inductance is the henry.12
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Joseph Henry…important principles of electricity, including self-induction, a phenomenon of primary importance in electronic circuitry.
Read More…important principles of electricity, including self-induction, a phenomenon of primary importance in electronic circuitry.
Read More- electromagnetismFaraday’s discovery of electric induction
…Henry reported and correctly interpreted self-induction. He had produced large electric arcs from a long helical conductor when it was disconnected from a battery. When he had opened the circuit, the rapid decrease in the current had caused a large voltage between the battery terminal and the wire. As the…
Read More…Henry reported and correctly interpreted self-induction. He had produced large electric arcs from a long helical conductor when it was disconnected from a battery. When he had opened the circuit, the rapid decrease in the current had caused a large voltage between the battery terminal and the wire. As the…
Read More