Inductor

Opposing changes in current, an inductor stores energy in its magnetic field and has an impedance that grows with frequency. In the circuits listed here inductors appear in RL time-constant experiments, series and parallel RLC resonance, AC phase-shift measurements, and filters, and as the coil whose stored energy produces a voltage spike when switched off, which a flyback or freewheeling diode suppresses. For example, "RL-LC-RC-RLC-C Response" switches different combinations of resistor, inductor and capacitor so their transient responses can be compared on the oscilloscope.