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Dynamic resistance
Posted to the Waveform Library on 5/31/2023

Fan motor has .3 ohms resistance. Oscilloscope indicates initial current just before fan rotates is 46.66 amps @ 14 volts. I = E/R =14/.3 = 46.66 amps. When rotating normally the fan current is 5 amps. Therefore the CEMF produced by the rotating fan is 12.5 v...