We consider the motion of a cylinder with the same mass and size as a curling rock, but with a very different contact geometry. Whereas the contact area of a curling rock is a thin annulus having a radius of 6.25 cm and width of about 4 mm, the contact area of the cylinder investigated takes the form of several linear segments regularly spaced around the outer edge of the cylinder, directed radially outward from the center, with length 2 cm and width 4 mm. We consider the motion of this

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... as it rotates and slides over ice having the nature of the ice surface used in the sport of curling. We have previously presented a physical model that accounts for the motion of curling rocks; we extend this model to explain the motion of the cylinder under investigation. In particular, we focus on slow rotation, i.e., the rotational speed of the contact areas of the cylinder about the center of mass is small compared to the translational speed of the center of mass. The principal features of the model are (i) that the kinetic friction induces melting of the ice, with the consequence that there exists a thin film of liquid water lying between the contact areas of the cylinder and the ice; (ii) that the radial segments drag some of the thin liquid film around the cylinder as it rotates, with the consequence that the relative velocity between the cylinder and the thin liquid film is significantly different than the relative velocity between the cylinder and the underlying solid ice surface. Since it is the former relative velocity that dictates the nature of the motion of the cylinder, our model predicts, and observations confirm, that such a slowly rotating cylinder stops rotating well before translational motion ceases. This is in sharp contrast to the usual case of most slowly rotating cylinders, where both rotational and translational motion cease at the same instant. We have verified this prediction of our model by careful comparison to the actual motion of a cylinder having a contact area as described.