Effects in a Two-Velocity Dynamical System Associated with the Coincidence of the Velocities in an Interval

The behavior of the principal singularities of the fundamental solution of the problem for a dynamical system in which two components of the wave propagate with different velocities is studied. We show that the principal singularities of the wave can pass from one component to the other whenever in the system there exists an interval in which the velocities of propagation coincide for both components.