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## Main Question or Discussion Point

Hi Friends,

Two particularly abstract queries have surfaced in my mind (this seems to be a recurring problem with me! )

Let us consider an 'ideal' solenoid coil (zero resistance, pure inductance). It is connected to an AC supply of say, 220VAC, 50Hz. Now assume that the medium (or magnetic core) surrounding the coil presents 'zero' reluctance to the magnetic flux. Hence, the magnetic flux embracing the coil will be 'infinite'. This would result in an infinite inductance and hence, an infinite inductive reactance! Now, under these conditions, ideally, the current thru the coil must be 'zero'.

The problem is, it is pretty difficult to visualize this situation, as even to create an infinite magnetic flux, some finite amount of magnetizing current must flow thru the coil. But, as per the theoretical concept, infinite inductance means current thru the coil should be an absolute zero! This cannot be realized even by examining the voltage versus current waveform of a pure inductor where current lags supply voltage by 90 deg. Hence, plz help!

Similarly, consider an 'ideal' capacitor (zero resistance, pure capacitance). (The ideal capacitor could also be considered as a single charged conductor with the opposite conductor assumed to be placed at infinity). It is connected to an AC supply of say, 220VAC, 50Hz. Now assume that the dielectric medium between the capacitor plates presents 'zero' permitivitty to the electric flux. Hence, the electric flux between the capacitor plates would be 'zero'. This would result in 'zero' capacitance and hence, an infinite capacitive reactance! Now, under these conditions, ideally, the current thru the capacitor must be 'zero'.

Again, it is pretty difficult to visualize this situation, as the capacitor plates ideally cannot hold any electrical charge (zero capacitance) as mentioned above. Under this condition, can I replace the capacitor plates with point charges of opposite polarities placed in this special dielectric medium......as point charges ideally present 'zero' capacitance? As per the theoretical concept, 'zero' capacitance means current thru the capacitor should be an absolute zero! This cannot be realized even by examining the voltage versus current waveform of a pure capacitor where current leads supply voltage by 90 deg.

Valuable inputs are very much awaited for the same.

Thanks & Regards,

Shahvir

Two particularly abstract queries have surfaced in my mind (this seems to be a recurring problem with me! )

**CASE 1 :- Infinite Inductance**Let us consider an 'ideal' solenoid coil (zero resistance, pure inductance). It is connected to an AC supply of say, 220VAC, 50Hz. Now assume that the medium (or magnetic core) surrounding the coil presents 'zero' reluctance to the magnetic flux. Hence, the magnetic flux embracing the coil will be 'infinite'. This would result in an infinite inductance and hence, an infinite inductive reactance! Now, under these conditions, ideally, the current thru the coil must be 'zero'.

The problem is, it is pretty difficult to visualize this situation, as even to create an infinite magnetic flux, some finite amount of magnetizing current must flow thru the coil. But, as per the theoretical concept, infinite inductance means current thru the coil should be an absolute zero! This cannot be realized even by examining the voltage versus current waveform of a pure inductor where current lags supply voltage by 90 deg. Hence, plz help!

**CASE 2 :- Zero Capacitance**Similarly, consider an 'ideal' capacitor (zero resistance, pure capacitance). (The ideal capacitor could also be considered as a single charged conductor with the opposite conductor assumed to be placed at infinity). It is connected to an AC supply of say, 220VAC, 50Hz. Now assume that the dielectric medium between the capacitor plates presents 'zero' permitivitty to the electric flux. Hence, the electric flux between the capacitor plates would be 'zero'. This would result in 'zero' capacitance and hence, an infinite capacitive reactance! Now, under these conditions, ideally, the current thru the capacitor must be 'zero'.

Again, it is pretty difficult to visualize this situation, as the capacitor plates ideally cannot hold any electrical charge (zero capacitance) as mentioned above. Under this condition, can I replace the capacitor plates with point charges of opposite polarities placed in this special dielectric medium......as point charges ideally present 'zero' capacitance? As per the theoretical concept, 'zero' capacitance means current thru the capacitor should be an absolute zero! This cannot be realized even by examining the voltage versus current waveform of a pure capacitor where current leads supply voltage by 90 deg.

Valuable inputs are very much awaited for the same.

Thanks & Regards,

Shahvir