Abstract: From the perspective of dynamics，this paper conducts a theoretical analysis on the third

problem of the 2018 International Young Physicists’Tournament ( IYPT2018) ，“Dancing Coin”，and

obtains the change in the height of the coin over time during a single beating. At the

same time，the concept of “place error”is pro- posed，and the influence of coin place error

on the coin’s tilting height is further discussed. It is found that the greater the

place error，the faster the coin will rotate and the greater the maximum height of the

coin will be reached. In the experiment，the process of coin dancing under different place

errors was recorded with a high-speed camera，and software tracker was used to track. The

comparison between the experimental results and the theoretical model verifies the

correctness of the theoretical model.

Key words: dynamics, IYPT, dancing coin, place error