Stationary waves can be related to long line of chinese dancers making a S formation. If the the 2 ends and the middle persons do not move , they would form the node. The first half will move in the opposite direction to the second half of the line. This would require the dancers to move in the same phase between the 2 nodes and in the 180 degrees out of phase for those in the adjacent node. As they are different distance from the centre line position some have to have a greater speed especially the dancer at the mid point between two nodes who also have the greatest amplitude. This formation is very beautiful to watch as there is symmetry in motion.
