The structures were fully optimized until the Hellmann-Feynman force on each atom was less than 0.01 eV/Å. The plane-wave function basis was used to expand the wave functions, and the energy cutoff was 500 eV. The 9 × 9 × 1 or 4 × 4 × 1 Monkhorst-Pack k mesh was generated ...
Then, the motion equation passes through a series of simplifications, and the distribution of shear stress at position y (y = R − r) can be given as: (6)τy=τac+τbo+τf The shear stress at position y consists of three components: acceleration, buoyancy and friction....
A 46.7-kg skater is standing at rest in front of a wall. By pushing against the wall she propels herself backward with a velocity of -1.78 m/s. Her hands are in contact with the wall for 0.805 s. Ignore friction and wind resistance...