SELF

86

S.B. Karavashkin and O.N. Karavashkina

Analysing the experimental result further, we have to mark that lower the frequency 80 kHz which we chose above, the resonance processes in the secondary loop are over and we can reliably observe the variation of emf induced in this loop with the transformation of this last. The diagram of emf for the low-frequency part of range is shown in Fig. 15.

Fig. 15. The amplitude of induction emf with respect to the frequency f of current in the primary loop and distance h from the outer side of secondary loop from the core

In this plot we see that in all the low-frequency range the emf monotonously decreases with the distance h from the outer side of secondary loop to the core. This means that with the growing size of secondary loop and, accordingly, with growing quantity of force lines of magnetic field crossing this loop, the emf falls. This opposes the prediction which followed from the Maxwell formulation.

To analyse the obtained results from the view of Faraday approach, we have to take into account that in accordance with this approach, the induction emf is excited, resulting from direct affection of the strength of magnetic field in the region of loop wires, with electrons of loop wires. Proceeding from such approach, in case of considered experimental set, the emf is excited only in the inner and outer sides of loop. Lateral sides practically do not participate in induction, as they specially were considerably distanced from the core. So, when the outer side is closer to the core, the emf is excited in both sides of secondary loop. And when the outer side is maximally distanced from the core, the emf in it does not excite, the same as in the lateral sides, because, as we revealed in the first experiment, the amplitude of magnetic field strength is in this region practically zero. From this, to determine the emf induced in the outer side of loop, we have to subtract from the values of emf for all intermediate h the values of emf for maximally distanced position of the outer side.