Comment on 'Improved pivot-slide model of the motion of a curling rock'

摘要

We point out three errors in a recent paper that is based on one of our two papers. Together our two papers describe a first-principles "pivot-slide model" of the motion of a curling rock. The most serious error is that the "improved pivot-slide model" (Mancini and de Schoulepnikoff. Can. J. Phys. 97(12), 1301 (2019) doi:10.1139/cjp-2018-0356) is based on only our first paper, whereas the most important work in our model was described in our second paper, which those authors have overlooked. Another error is that the authors claim we use constant friction, whereas we actually use a velocity-dependent formulation of the ice friction coefficient. Thirdly, the authors use a time-dependent function for the ratio of pivoting time to sliding time, whereas in our second paper, we showed from first principles that this ratio does not depend on time.