Rotational analogue of impulse. It is equal to the sum of moments of momentum and of proper kinetic moment (sometimes called “dynamic spin”). Kinetic moment of a body is calculated relatively to a fixed point in a system of reference and depends upon the chosen “pole” (another point, fixed in the body). For a rigid body, if its center of mass is taken as a “pole,” and the origin of an inertial system of reference is taken as a fixed point, the kinetic moment is equal to r x p + J ω, where r is the radius-vector of the center of mass, p is the momentum (impulse) of the body, J is the tensor of inertia calculated relative to the center of mass, and ω is the angular velocity of the body. The time derivative of the kinetic moment represents the inertial term in the law of balance of torque (the torques must be calculated relative to the same fixed point). In micropolar theories, the existence of proper kinetic moment of particles and resistance of the medium to their rotation causes the existence of rotational waves