Babban Rattleback, Dutse na Celtic

Girman 9.6x2x1cm, Shiryawa 16.5x9x1cm, PVCA rattleback, wanda aka fi sani da

Dutsen kadi, wanda aka fi sani da dutsen Celtic, babban tsalle ne mai tsalle-tsalle. Zai juya cikin takamaiman alkibla; duk da haka, lokacin da aka juya shi a wata hanya ta baya, zai zama mara ƙarfi, girgiza, tsayawa, sannan canza zuwa juyawa zuwa ainihin takamaiman shugabanci.
Wannan lamarin juya-juya-juyawa da alama ya keta dokar kiyayewa na saurin kwana a kimiyyar lissafi. Abin da ya fi ban mamaki shi ne cewa lokacin da muka juya gyroscope zuwa takamaiman alkiblarsa, yawancin gyroscopes ba za su sami wannan sabon abu na musamman ba; zai faru a akasin haka. Waɗannan halaye guda biyu suna sanya saman juzu'i abu ne mai matukar wuya, wanda ya tayar da tunanin mutane da yawa tun zamanin da.