About This Tool
Sine Wave Interference visualises the principle of superposition — one of the most fundamental concepts in wave physics. Each coloured wave is a pure sine function with its own frequency (1.0×, 1.3×, 1.7×, or 2.2× a base frequency). The bright white curve is the algebraic sum of all active waves drawn together. Where the individual waves push in the same direction at the same moment, their amplitudes add up to produce constructive interference and a larger combined wave. Where they push in opposite directions, they partially or fully cancel each other out in destructive interference. The result is a complex, continuously evolving waveform.
How to Use
The animation starts automatically showing 3 superposed sine waves.
Use the Waves buttons (2, 3, 4) to add or remove individual frequency components and see how the sum wave changes.
Use the Speed buttons (Slow / Normal / Fast) to control how quickly the phase advances.
Press Pause / Play to freeze the display at any moment.
Watch the coloured individual waves and the white sum wave — notice how the sum spikes where waves align and flattens where they cancel.
Frequently Asked Questions
What is wave superposition?
The principle of superposition states that when two or more waves overlap, the resulting displacement at any point is the simple algebraic sum of the displacements of the individual waves. This applies to sound, light, water waves, and electromagnetic signals.
What is constructive vs destructive interference?
Constructive interference occurs when waves are in phase — their peaks and troughs align — producing a larger amplitude in the sum. Destructive interference occurs when waves are out of phase — a peak of one coincides with a trough of another — reducing or cancelling the combined amplitude.
What do the different colours represent?
Each colour is a separate sine wave at a fixed frequency multiple: blue at 1.0×, purple at 1.3×, green at 1.7×, and amber at 2.2× the base frequency. The white curve is always their sum.
Why are the frequencies not round numbers like 1, 2, 3?
Using incommensurable (non-integer) ratios like 1.0, 1.3, 1.7, 2.2 means the combined wave never exactly repeats, producing a richer and more visually interesting interference pattern than simple harmonic series would.