A metal string of length 1.20m is clamped rigidly at both ends. When it is driven at its third harmonic, the wave pattern along the string is observed with the unaided eye.
Answer the following questions about the standing wave that forms.
(1) Describe the spatial arrangement of nodes and antinodes along the string for the third harmonic. In your answer, indicate the distances from one end of the string at which each node and each antinode is located.
(2) Explain, in words, how the superposition of two identical waves traveling in opposite directions along the string gives rise to the node–antinode pattern you described in part (a). Your explanation should make clear why displacement is always zero at each node and maximum at each antinode.