Ohm's Law Analogy Research Articles

Resistance to Flow in Vascular Beds

CARLILL'S attempt1 to dispel confusion in the use of the Ohm's law analogy in blood circulation theory requires further clarification, since it is only the incorrect application of this analogy that needs to be abandoned not the analogy itself, but it raises an important point. This is confirmed by Burton2 when he insists that, for vascular circuits: Resistance to flow (R) = For a definition consistent with the electrical analogy we must have R = (P—p)/F where p is the critical closing pressure as referred to by Carlill. This gives F = P/R — p/R, which is of the form y = mx — c since p/R is constant for any single one of the lines in Carlill's Fig. 1 and gives the same result for dF/dP as in Burton's equation (4) derived from his incomplete expression of form y = mx.

The theory of the telephone receiver

The equations connecting the winding current and diaphragm motion of a telephone receiver under impressed simple harmonic electromotive and mechanical forces are formulated under: (I) The Maxwell flux theory; (2) the magnetizing-winding theory; (3) the Ampèrean resistanceless fixed molecular circuit theory of permanent magnetism; and (4) a general molecular orbital theory of ferromagnetism. On the latter theory it is found that the coupling coefficients M and N in the equations in question are in general different, in counter-distinction to the other three theories as hitherto formulated. The flux theory is shown not to be inconsistent with this result when certain dynamical phase relations are introduced into the static flux-magnetomotive force formula (Ohm's Law analog) always employed in this theory. The Ampèrean rigid circuit theory is criticized as an inadequate dynamical representation of ferromagnetism. The magnetizing-winding theory (dynamical) is reproduced in slightly generalized form.