The apparent force in a rotating system, deflecting masses radially outward from the axis of rotation, with magnitude per unit mass ω2R, where ω is the angular speed of rotation and R is the radius of curvature of the path. This magnitude may also be written as V2/R, in terms of the linear speed V. This force (per unit mass) is equal and opposite to the centripetal acceleration. The centrifugal force on the earth and atmosphere due to rotation about the earth's axis is incorporated with the field of gravitation to form the field of gravity.