How Strings Vibrate

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Handdrawn stick figure with a guitar imagining the string vibrations as jump-rope-like sine waves.

Illustrated diagram of the sine waves superposed inside a triangular plucked string.

Two views of guitar strings vibrating after being plucked (left) or struck (right). Both views are looking up the neck from the bridge.

Many of us have a mental image of strings vibrating like a swinging jump rope, but that’s not quite what you actually see. Instead, plucked strings often look strangely triangular, as Henry explains in this Minute Physics video. This more complicated shape comes from the way the string’s tension responds to the applied force of plucking, striking, or bowing.

That doesn’t mean that the jump rope picture is entirely wrong, though. The triangular waves seen in the video are the shape you get when all the sine waves of the jump rope model get added together! (Superposition is fun.) (Video and image credit: Minute Physics)