SELF

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S.B. Karavashkin and O.N. Karavashkina

To visualise, we show in Fig. 10 in different views the 3 D diagram plotted on the basis of data shown in Table 1.

Fig. 10. The induction emf of the outer secondary loop against the frequency f of alternating current and distance h from the nearer side of this loop to the lateral side of core

In this diagram we see two features. First, at the frequency band 170 kHz we see the resonance peak which abruptly increases the induction emf at the measured distances from the core. This tells that, in order this peak to be unable to distort the measurement, we have to study the inductance at the range well less than the resonance peak frequency.

In Fig. 11 we show the close-up of low-frequency part of the diagram shown in Fig. 8, 200 Hz to 80 kHz.

Fig. 11. The low-frequency part of diagram shown in Fig. 8 (200 Hz to 80 kHz)

We see in this diagram that in the region of core the magnetic field monotonously falls with the distance from loop to the core. The decrease is strongly nonlinear; in accordance with the above study, this enables us to reveal the interaction of each side of loop with the magnetic field of core. However, before we obtain the results of the second, main experiment, we may not conclude, nor analyse. We only can indicate a considerable nonlinearity of magnetic field in the near of core, which limits us to the band up to 80 kHz, in order to obtain the reliable information about the induction emf in the secondary loop, when we carry out the main experiment.