Agate is good protective energy stone, especially for children, and is very calming and soothing. It also can help strengthen the body's connection to the earth.
The friction factor, f, is a dimensionless factor that depends primarily on the velocity u, diameter D, density Ï, and viscosity Î·. It is also a function of wall roughness which depends on the size Îµ, spacing Îµ' and shape of the roughness elements characterized by Îµ''.
These factors are: 1  Surface Finish â The number, roughness and even the directional contact points of the asperities on the surfaces can dramatically affect the frictional coefficient. 2  Temperature â Both ambient and operational temperature can affect friction. 3  Operational Load â Friction varies directly with load.