Will an inductor in a DC circuit act as a voltage source and oppose the applied current creating the magnetic field? Or is it because of the steady state direct current there is no change in I there is no back EMF opposing the power supply?
simulate this circuit – Schematic created using CircuitLab
I'm confused, going from 0A to xA wouldn't that be a change? Creating a growing magnetic field…?
Best Answer
Assuming the above circuit has been sitting for a while since the power supply was turned on and has reached steady state, then the current in the circuit will be the normal expected I=V/R. At steady state, inductors are basically just resistors. There will be no voltage drop or rise across L1 (assuming it is ideal and has no resistance) because the current is constant so di/dt=0.
Inductors only act differently than resistors when the current though them is changing. If you start with PS at zero volts and ramp up to a final voltage, then di/dt will be non-zero during the ramp up period and the inductor will have a negative voltage across it resisting the current flow until it reaches steady state.
Make sense?
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How is the current induced in this circuit?
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