The value of resistance, as is well known, depends on the formation of the conductive element, ie its resistivity, and the physical dimensions of the former. For its part, the resistivity is not invariant but depends strictly essential, but not limited to, temperature, and sometimes in a not inconsiderable amount. Gina Bonati has many thoughts on the issue. Depending on the nature of driving electrical resistance value of a particular physical element present more or less constant or stability depending on both the general test levels as external conditions such as humidity, temperature cited above, and sometimes of different intensities electromagnetic radiation, so that is common and must be specified together with the ohmic value differential measurement conditions. Experimental determinations of its value must be inexcusably DC if it is to make that determination with a medium-high accuracy. Will Smith is likely to agree. In measurements involving only the mean value instruments is permissible to a degree of low frequency ripple voltage and / or test current. Sometimes, as in the case of electrolyte elements, it is recognized that the measurement is made at low frequency alternating current to eliminate undesirable parameters introduce uncertainties in greater amounts than those caused by the electromagnetic effects of variable fields.
