Rubber rope stretched across front of room.

The Rubber Rope: Transverse Travelling Waves, (and Standing Waves). Attach one end of the rubber rope to the hook on the wall and stretch the rope across the front of the room. Quickly move the hand up or down once so as to give a pulse to the rope. (The rope should be fairly taut.) The pulse travels to the end and back again, being reflected from the stationary end without disturbing the wave motion. You may also use this rope to illustrate standing waves. Move the end periodically up and down with a slow motion; changing this period until the rope shows just two loops with a node in the center. Increase the up and down period to get three loops and two nodes, etc.