Upward rolling double cone
The upward rolling double cone is a physical experiment in which a double cone appears to roll up an inclined plane .
construction
The inclined plane used for the experiment consists of two rails that are arranged in a V-shape and together form a predetermined angle. The ends of the rails, where the distance between the rails decreases, form the lowest point of the inclined plane. The ends with the greater distance form their highest point. If a double cone, consisting of two cones connected axially symmetrically at their base , is placed at the lowest point of the inclined plane, its axis of rotation and thus also its center of gravity are initially in its highest position. Since the rails diverge in the rolling direction, the axis of rotation can assume an ever lower position when the double cone appears to roll upwards. The axis of rotation of the double cone is lower between the rails at the end of the distance covered than at the beginning of the action. The double cone can only roll up the inclined plane because its center of gravity moves downwards when rolling on the rails. When looking closely at the rolling cone from the side, the downward movement of the axis of rotation can also be observed directly. The condition under which this movement can take place depends on the opening angle of the cone as well as the opening angle and the slope angle of the rails.
A double cone consisting of two cones ( diabolo ) connected axially symmetrically at their tips can also be used to carry out the experiment. The inclined plane must be adjusted accordingly.
history
The experiment is first described in the work "Physices elementa mathematica, experimentis confirmata, sive introductio ad philosophiam Newtonianam" (Leiden 1720) by the Dutch physics professor Willem Jacob 's Gravesande .
useful information
The experiment is described in various books for school experiments. It has also found its expression as an exercise for physicists.
The game of skill "Sisyphus" was realized according to the principle of the double cone rolling upwards. However, a ball is used here instead of the double cone.
literature
- WJ's Gravesande: Physices Elementa Mathematica Experimentis Confirmata. Leiden 1720 ( digital version of the 2nd edition 1725 )
- H. Hahn: Physikalische Freihandversuche I. Verlag von Otto Salle, Berlin 1905
- G. Dussler: Games and toys in physics lessons. Verlag Otto Salle, Frankfurt am Main 1933
- A. Friedrich: Handbook of experimental school physics. Volume 2. Aulis Verlag, Cologne 1962
- H. Mitter: Mechanics, lectures on theoretical physics 1. BI-Wissenschaftsverlag, Mannheim 1989
Web links
- Technical University of Munich (PDF file; 239 kB)