Μια υπηρεσία της Σπηλαιολογικής Ομοσπονδίας Ελλάδος για όλους τους Έλληνες σπηλαιολόγους
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Λοιπόν....caspex έγραψε:Καλημέρα!
Όποιος δεν ξέρει το Pit Sounder, δεν ξέρει τι χάνει....
Ποιός θα προσπαθήσει???
Για να βοηθήσω, χρειάζετε Palm για να δουλέψει!!!!
](./images/smilies/eusa_wall.gif "Brick wall"){kind=small}
Τι κάμερες και αηδίες. 
Τι μηχάνημα χρησιμοποιείς για να λάβεις τον ήχοΠαναγιώτης έγραψε:Με τον κατάλληλο υπολογισμό, βγάζουμε επιστημονικό τρόπο το βάθος.
από το crash του palm και να σου δώσει τα αποτελέσματα; Σωστά καταλάβατε. Βοηθάει στον υπολογισμό του βάθους ενός βαράθρου με την γνωστή μέθοδο του ..."λιθοβολισμού"!!!The Pit Sounder form
This form allows estimating the depth of a pit from the fall time of a rock. Computations lay on the numerical resolution of the differential equation that describes the fall of a spherical body in air. The parameters of this equation are the mass and diameter of the rock, Earth's gravitational constant, air density and the Reynolds number of a sphere, that in turn depends on the diameter and instantaeous speed of the rock, as well as air density and viscosity.
A more complete explanation of the maths involved is available in the profondeurpuits.pdf document (in French) in the Auriga Web site. ( http://www.speleo.qc.ca/auriga )
Only the rock diameter is input by the user. The rock mass is computed from this diameter, using the average limestone density of 2520 kg per cubic meter. The gravitational constant used corresponds to a 45° latitude at the surface of the Earth. Air density and viscosity depend on temperature and humidity, but values used correspond to 20° Celsius in a saturated atmosphere (100% humidity.)
The equation solution yields the distance travelled by the rock over time with the help of a constant-step 4th order Runge-Kutta method. The computed pit depth takes into account the speed of sound in air.
Find a rock, ideally spherical, and select its Diameter with the scroll bar.
At the moment the rock is dropped (with no initial speed), hit the Rock! button or one of the 4 hardware application buttons to start the stopwatch.
When the sound of the rock hitting the bottom of the pit is heard, hit the Boom! button or one of the 4 hardware application buttons to stop he stopwatch. The estimated depth is displayed after computations that can last a few seconds. The algorithm accepts fall times of up to 15 seconds.
It is possible to manually input a fall time measured outside of Auriga by tapping the stylus on the time field to make it editable and to write that fall time. Hit the Boom! button to know the corresponding depth.
Research and algorithm: Pierre Beauchemin
Menu: none.
