Velocity Waves at a Rigid Termination

Since the displacement is always zero at a rigid termination, the velocity is also:

$$v(t,0) \equiv 0 \qquad v(t,L) \equiv 0$$

Therefore, velocity waves reflect from a rigid termination with a sign flip just like displacement waves:

$$v^{+}(n) = -v^{-}(n)$$

$$v^{-}(n+N/2) = -v^{+}(n-N/2) \protect$$ (5.10)