W.2.1 Rubber Hose or Wave Spring

Clamp a wave spring or rubber hose to the table and you can send a pulse along and see it reflected. The brass spring works best. Free end reflection can be accomplished by attaching a 1/2 meter long string to the end of the spring. If the end of the hose or wave spring is laid on the floor, you can send a pulse down and have it absorbed with no reflection.