We study the quantum Vavilov-Cherenkov (QVC) radiation and quantum friction occurring during motion of a small neutral particle parallel to a transparent dielectric plate with the refractive index n. This phenomenon occurs above the threshold velocity vc = c/n. The particle acceleration and rate of heating are determined by the friction force and heating power in the rest reference frame of the particle. We calculate these quantities starting from the expressions for the friction force and the radiative energy transfer in the plate-plate configuration, assuming plate at the rest in the lab frame rarefied. Close to the light velocity there is a big difference between the friction force and the radiation power in the rest frame of a particle and in the lab reference frame. This difference is connected with the change of the rest mass of the particle due to absorption of radiation. Close to the threshold velocity the decrease of the kinetic energy of the particle is determined mainly by radiation power in in the lab frame. However, close to the light velocity it is determined also by the heating power for the particle. We establish the connections between the quantities in the different reference frames. For a nanoparticle the QVC radiation intensity can be comparable to classical one. We discuss the possibility to detect QVC radiation.
We study the friction when a rectangular tire tread rubber block is slid on an ice surface at different temperatures ranging from −38○C to −2○C, and sliding speeds ranging from 3 µm/s to 1 cm/s. At low temperatures and low sliding speeds we propose that an important contribution to the friction force is due to slip between the ice surface and ice fragments attached to the rubber surface. At temperatures above −10○C or for high enough sliding speeds a thin premelted water film occur on the ice surface and the contribution to the friction from shearing the area of real contact is small. In this case the dominant contribution to the friction force comes from viscoelastic deformations of the rubber by the ice asperities.
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