The Rate of Sliding and the Analysis of Friction on Snow Part IV

Abstract

Using the rotation friction instrument, we tried the measurement of friction of crushed ice and found that the friction of plastics, paraffin, skiing wax may will be studied in an ordinary laboratory by the use of crushed ice instead of snow.Thus much information about the friction of snow and crushed ice was obtained, we finally used organic crystals in place of snow and measured friction in the neighbourhood of theirmelting point.In this case, μS and μK at low temperatures were found to take nearly the same values as in the case of snow and to decrease gradually as the temperature approaches the melting point of organic crystal. Above melting point, excess melt showed abnormal increase of μK and decrease of, μS as the case with snow.From old times, the phenomena due to the friction of snow has been considered as quite peculiar to snow, but the above mentioned data show that these phenomena are common to all kinds of crystals, organic and inorganic. It is true, in the case of snow crystal, molten crystal water absorbed by sliding surface or suspended between sliding surface and compressed snow layer causes more complication, but it has now been shown that the same sort of complication arises also in the frictional phenomena of other kind of crystals in the neibourhood of their melting point.