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View attachment untitled-1.pdf

So the phase shift for the emf minus the phase shift for the current should give pi/2, but it doesn't! The values I got were (1.103-1.977)=-0.874

What is going on?

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- #1

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View attachment untitled-1.pdf

So the phase shift for the emf minus the phase shift for the current should give pi/2, but it doesn't! The values I got were (1.103-1.977)=-0.874

What is going on?

- #2

NascentOxygen

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How did you measure the phase relation of current to voltage?

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Loggerpro graphed both simultaneously (using a sin function for each). The general form for each equation was Asin(Bt+C)+D. I found C for each graph and then took the difference. Does that answer your question?How did you measure the phase relation of current to voltage?

- #4

NascentOxygen

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Yes, 60 Hz

number of turns of outer coil- (2920 pm 1)

number of turns of inner coil-(235 pm 1)

diameter of outer coil-(3.4200E-2 pm 7.8E-5) meters

diameter of inner coil- (1.7300E-2 pm 7.8E-5) meters

Length of inner coil- (12.000E-2 pm 7.8E-4) meters

Length of outer coil- (11.000E-2 pm 7.8E-4) meters

All 95% tri pdf

Emf max=2.270V

I also have values for the resistance, capacitance and inductance (from the manual, not from measurement)

Outer coil #29 wire, approx .29mm

Inductance: 63 pm 3 mH

Resistance 76 pm 2 Ω

Capacitance: 124 pm 2 pF

Inner coil #18 wire approx 1mm

Inductance: 78 pm 22 μH

Resistance: 0.4 pm 0.1 Ω

Capacitance: 142 pm 2 pF

I have a suspicion that this has to do with the resistance of the coils, but I still don't understand why or how the model I used is flawed. The predicted result was almost a perfect match with the actual result except for this shift.

- #6

NascentOxygen

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How many mm is that?diameter of outer coil-(3.4200E-2 pm 7.8E-5) meters

Anyway, my suggestion for the phase not being as expected hinges on there being capacitive coupling between the coils, in addition to the inductive coupling. Capacitive coupling gives a phase shift different from the transformer coupling. Added to this, there is always inductive coupling from power cables in the wall, and this may not have the same phase as the sinewave that is driving the solenoid here. The latter interference is more pronounced in high impedance circuits, and I surmise that the load on your sensing coil is the high input impedance of a voltmeter?

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