Originally posted by pha3z
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Self-inductance IS Counter EMF.
Counter emf is present whenever there is current flow in a conductor.
IF self inductance is counter emf as you say then are you saying that counter emf is stored in the coil ?
The current delay from self inductance is merely the building of the magnetic field around the coil before current can flow through the closed loop circuit.
Whenever there is emf producing current flow in a conductor there is counter emf there to oppose it. Lenz's law holds.
To give an analogy using a tennis ball, a person and the air, if the wire is like air (the conductor), the movement of the ball is the current and the emf is the person.
When the person throws the ball in air he uses emf to produce current (moving ball) when the ball is moving (current) there is air resistance (counter emf). If you are throwing the ball in air, air resistance cannot be avoided, self inductance would be like instead of throwing the ball the ball is placed at the end of a spring and the spring is compressed by the emf as the spring is compressing there is counter emf produced because of the moving ball (air resistance) and when the spring decompresses it produces emf to make the ball move (current) the moving ball is opposed by counter emf (air resistance), whenever the ball moves in air there is air resistance.
Self-Inductance
That link says that the self inductance and current causes the magnetic field size/intensity and the magnetic field in turn causes "more" counter emf, the self inductance is not the counter emf it just causes the magnetic field that causes "more" counter emf because of the magnetic field building. The key thing is that it causes more counter emf not all of it.
The way I see it the value of self induction will determine the size/intensity of the magnetic field built, even if the self inductance is cancelled by capacitance there is still counter emf when the current flows.
If you have broken Lenz's law and can put current through a wire with no counter emf then please show us.
Cheers


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