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The objective of this research was to determine the coefficient of restitution of spherical pellets. When the spherical pellets with a density of 0.1 - 0.9 g / cm3 were dropped on two types of flooring materials (wood floor and ceramic floor) with a density of 0.7 and 2.6 g / cm3 respectively, the results showed that; 1) When the height of the spherical pellets dropping was increased, the coefficient of restitution decreased. At the height of 14 cm, the least coefficient of restitution was found for both wood floor and ceramic floor. 2) When the spherical pellets which made from the same material but had different diameter were dropped at the same height of 10 cm, the coefficient of restitution was the same, and it decreased when the density ratio of the spherical pellets to flooring materials was increased. 3) When dropped the spherical pellets on the granular materials which were overlaid in 4 layers, the more number of layers, the less coefficient of restitution was found. It was because the spherical pellets restituted on the 4th layer less than the 1st layer.
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