True angle

Other projections are possible, but crystallographers use the stereographic projection because the angles between planes in the projection are the true angles between the planes. 

A polarimeter has a zero error of -0.1°, i.e. it reads -0.1° when the true angle of rotation is zero. What is the true angle when the polarimeter reads ... 

Therefore, later research concluded " that material is entrained at some other angle—the true angle of nip —which is smaller than the angle of friction and must be determined experimentally. The use of an empirical angle of entrainment makes allowances for the upward movement of material avoiding the squeeze after compaction has commenced. 

As already mentioned, the interpretation of data on static contact angles must be done with the understanding that the system in question has been sufficiently weU controlled so that the angle measured is the true angle and not a reflection of some contaminant on the sohd surface or in the hquid phase of interest. Contact angles, for example, can be extremely useful as a... 

Minimum valley angle in convergent section = 60°. Note the valley angle is the true angle to the vertical of the line of intersection between two adjacent sides. 

Even though vertical standpipes can transfer solids more efficiently than hybrid angled standpipes, true angled standpipes (those containing no vertical section) are commonly operated satisfactorily in large... 

A and Ay are calculated from the spectra. The true angle, a, that the beam makes with the sample is found by correcting the measured angle for the refraction resulting from the refractive index [26]. 

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