An electric current flowing through a generates a magnetic field surrounding it. The generated by a given current depends on the geometric shape of the circuit. Their ratio defines the inductance . Thus .The inductance of a circuit depends on the geometry of the current path as well as the When an inductor is open-circuited, it generates a spark due to the sudden interruption of current, releasing energy equivalent to what was stored in the inductor. This occurs because an inductor cannot maintain current flow in an open circuit, leading to a rapid discharge of energy.
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