Tenths of a second
In many measurements of visually or acoustically perceptible events, the tenth of a second corresponds to the achievable accuracy; it is a tenth of a second.
Measurement problems
Research into time perception revealed different thresholds, depending on the phenomenon to be observed. In the case of simple, visually or acoustically observed time intervals , it is less than a tenth of a second, but this also includes the reaction time . The latter amounts to between 0.3 and 1 second , depending on the level of attention (see also moment of shock ).
In the case of manual stopping - manual time measurement with a mechanical or digital stopwatch - the average response time is 0.2 to 0.4 seconds. If an event can be precisely foreseen, for example when observing a star in a telescope, it can drop to less than 0.1 s with appropriate experience .
Because this reaction time fluctuates somewhat depending on the person and their current condition, manual stops are carried out by several judges in sporting competitions . In the case of inexperienced persons, the measured time spans are accurate to about 0.3 to 0.5 seconds, while 0.1 to 0.2 seconds can be achieved with long-term activity.
Manual stopping is also used in astrometry and in some areas of technology, unless the highest accuracy is required. In the laboratory, manual time measurements to ± 0.1 seconds are possible if one is experienced and in a balanced state. For precisely foreseeable moments (e.g. when star passages or very regular phenomena) one can even approach 0.03 seconds, which often eliminates the need for radio-controlled or electronic time measurement . When stars are covered by the moon, the element of surprise is partially retained (i.e. a reaction time of 0.3 seconds on average), but it usually only fluctuates by less than 0.1 s.
This can be explained by studies, according to which the 0.3s is composed of three partial reactions, each of which is about 1 tenth of a second: the sensory conduction time , the central cognitive processing time and the motor conduction time. In the case of simple stimuli, 1–2 of these components are omitted, so that the reaction time to acoustic stimuli is around 0.14 s and tactile 0.13 s.
The tenth of a second is also important in radio technology , for example with some time signal transmitters that code alternately with 1 and 10 Hertz . The perception of rattling noises and the time threshold for Morse code are in the same area .
literature
- Albert Schödlbauer : Geodetic Astronomy - Basics and Concepts. de Gruyter, Berlin 2000, ISBN 3-11-015148-0
- Gottfried Gerstbach: Analysis of personal errors in passage observations of stars. In: Geoswissenschaftliche Mitteilungen , Volume 7, pp. 51–102, Vienna 1975
- Manfred Horvat (ed.): The phenomenon of time . Conference proceedings, external institute of the Vienna University of Technology, 1976
