coupled motion

Rotations were allowed in one axis only, and coupled motions were prevented.

Coupled motion, separable forces, simple trajectory motion, trajectory motion with air resistance, motion of a particle in combined electric and magnetic fields (coupled equations).

Biot (1956a,b) has theoretically shown that a fluid saturated porous solid can sustain two types of P waves, with different propagation velocities, are dispersive and that each of these waves involve coupled motion in the fluid and the solid.