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''.
Friction is a force resisting slippage between two objects. The causes of it include gravity, electromagnetism, atomic and molecular attraction of charged particles, and so onâ¦. It is affected by the nature of the surfaces, such as smoothness, hardness, and state (solid, liquid, or gas).