Generation of electric fields by ice and snow friction

Strong electric fields up to 2×106 V/m having potentials up to 1.6 kV were generated in the gap between ice (or snow) and metallic and dielectric sliders, including alpine skis. Experimental data on the ice frictional electrification over wide ranges of sliding velocity and temperature are presented both for metal and dielectric sliders. Several possible physical mechanisms are discussed. The observed high magnitude of the potential difference V generated by friction between ice and sliders and the dependencies of V upon the slider velocity, ice conductivity, and temperature can be best explained in terms of high density electric charges picked up by a slider from the ice surface. The observed surface charge density corresponds to strong polarization of water molecules in the surface layer of ice. The phenomenon can play a significant role in forming a frictional force.