Standing Waves on a String

The Concept: Standing Waves

A standing wave is formed when two identical waves travel in opposite directions and interfere. On a string fixed at both ends, this happens when a wave reflects off the end and interferes with itself. At specific frequencies, called harmonics, the pattern becomes stable. Points that remain still are called nodes, and points of maximum oscillation are called antinodes.

How to Use the Lab

• The simulation shows a string fixed at both ends.
• Use the Harmonic buttons (n=1, 2, 3...) to automatically set the correct frequency to form a stable standing wave.
• Observe the stationary nodes and the oscillating antinodes for each harmonic.
• The "ghost" waves show the two underlying traveling waves that create the pattern.