Rigid body dynamics r and velocities v. Select a reference point R and compute the relative position and velocity vectors, The total linear and angular momentum vectors relative to the reference point R are and If R is chosen as the center of mass these equations simplify to To specialize these formulas to a rigid body, assume the particles are rigidly connected to each other so P, i=1...,n are located by the coordinates r and velocities v. Select a reference point R and compute the relative position and velocity vectors, where ω is the angular velocity of the system. The linear momentum and
Reduced mass a multitude of two-body problems, where classical mechanics is applicable. In a system with two point masses m and m such that they are co-linear, the center of mass may be found via formula_25. The moment of inertia of this system in the center of mass frame of reference is a two-body problem with two masses, each with its own distance to the center of mass. By converting to the equivalent reduced mass frame of reference, the system may be treated as a single reduced mass, μ, with a distance, d, equal to the sum of x and x. This