# Impact of the investigated system’s state on the equivalent measurements dispersion

2017;
: pp. 55-60
1
Lviv Polytechnic National University
2
Study in Wuhan Institute of Technology
3
Lviv Polytechnic National University, Ukraine

This paper presents the results of equivalent measurements of electrical resistance of two identical resistive coils. It is suggested that the difference between the RMS of investigated coils is formed as result of their non-equilibrium states. The energy spectrum of resistance fluctuations of investigated coils and the frequency range within which the energy spectrum changes unsignificantly, are determined.
There were defined the conditions based on the computed range of energy spectrum frequencies under which the implementation of measurement process is performed for quasi-equilibrium state of resistance and therefore the difference between the dispersions of the results of identical measurements is minimal.
One of the reasons of non-equilibrium state existence may be the defective internal structure of the objects. The results of this work can be used in the processing of statistical homogeneous measurements, as well as the identification of the influence of external factors. If the conditions for measuring – the number of measurements n and the time interval between measurements δt – are such that they satisfy the condition of quasi-equilibrium state of the system being studied, then the effect of external factors is the reason for the difference of variance.

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