Principle and History of Dilatometry

The unit for volume is the cubic meter. For density measurements this makes an unhandy, large sample, but one may remember that the g/cm is numerically identical to the SI unit Mg/ml For the present discussion, the experimental pressure is assumed to be constant and, if not indicated otherwise, is the atmospheric pressure (0.1 MPa). 

Variables length and volume length SI-unit is the meter, m volume SI-unit is the cubic meter, m (maintained as a multiple of a Kr radiation wavelength) 

Dilatometry under varying forces are the subject of thermomechanical analysis (TMA) and dynamic mechanical analysis (DMA), described in Sect. 4.5. The mass, needed for density measurement is always determined by weighing and is described in the discussion of thermogravimetry, TGA, in Sect. 4.6. 

The change of length and volume with respect to temperature is described by the expansivities a, respectively, as written in Fig. 4.10. Both are frequently 

The obvious length measurement is a side-by-side comparison with a standard meter, the obvious volume measurement, the evaluation of the content of a standard vessel. Early length measurements of this type were based on anatomical lengths. Naturally, the variation in human size was a basic problem that was solved either by averaging, or by arbitrary choice. The sixteenth century woodcut of how to produce a right and lawful rood is illustrated in Fig. 4.11. It shows that one should line up sixteen men, tall and short, as they happen to come out of the church after the service. One sixteenth of this rood was the right and lawM foot. It is surprising 

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