destructive interference

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Three graphs illustrate types of light wave interference. The top shows constructive interference with two waves combining to form a larger wave. The middle shows partial destructive interference, where the waves partially cancel, resulting in a smaller combined wave. The bottom shows complete destructive interference, where two waves of equal amplitude and opposite phase cancel each other out, resulting in a flat line.

$Diagram of a single-slit diffraction experiment showing light waves spreading through a narrow opening, creating alternating bright and dark bands on a screen. Insets show constructive and destructive interference, and a curve plots the brightest central band with weaker side peaks.$

Diagram of Young's double-slit experiment: light from one source passes through two slits, producing overlapping waves that create alternating bright constructive-interference and dark destructive-interference bands on a screen, matched by an intensity curve.

destructive interference

physics

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June 25, 2026

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interference — interference Interference.

In physics, destructive interference occurs when two or more wave trains moving on intersecting or coincident paths combine. This happens when waves are out of phase, meaning their vibrations are opposite. If two waves are of equal amplitude and completely out of phase, they can cancel each other out, resulting in a complete annulment of the wave. This phenomenon is the opposite of constructive interference, where waves in phase reinforce each other. Destructive interference is utilized in technologies like electronic mufflers to reduce noise by creating waves that cancel out unwanted sounds.12

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interference
…is maximum), the result is destructive interference, producing complete annulment if they are of equal amplitude. The solid line in Figures A, B, and C represents the resultant of two waves (dotted lines) of slightly different amplitude but of the same wavelength. The two component waves are in phase in…
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…is maximum), the result is destructive interference, producing complete annulment if they are of equal amplitude. The solid line in Figures A, B, and C represents the resultant of two waves (dotted lines) of slightly different amplitude but of the same wavelength. The two component waves are in phase in…
Read More

electromagnetic radiation
Superposition and interference
…superposition yielding zero intensity, is destructive interference. Since the resultant field at any point and time is the sum of all individual fields at that point and time, these arguments are easily extended to any number of superposing waves. One finds constructive, destructive, or partial interference for waves having the…
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…superposition yielding zero intensity, is destructive interference. Since the resultant field at any point and time is the sum of all individual fields at that point and time, these arguments are easily extended to any number of superposing waves. One finds constructive, destructive, or partial interference for waves having the…
Read More

interference fringe
…phenomena are called constructive and destructive interference, respectively. If a beam of monochromatic light (all waves having the same wavelength) is passed through two narrow slits (an experiment first performed in 1801 by Thomas Young, an English scientist, who inferred from the phenomenon the wavelike nature of light), the two…
Read More
…phenomena are called constructive and destructive interference, respectively. If a beam of monochromatic light (all waves having the same wavelength) is passed through two narrow slits (an experiment first performed in 1801 by Thomas Young, an English scientist, who inferred from the phenomenon the wavelike nature of light), the two…
Read More

radio telescope
Radio interferometry and aperture synthesis
…and out of phase (destructive interference) as Earth rotates and causes a change in the difference in path from the radio source to the two elements of the interferometer. This produces interference fringes in a manner similar to that in an optical interferometer. If the radio source has finite…
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…and out of phase (destructive interference) as Earth rotates and causes a change in the difference in path from the radio source to the two elements of the interferometer. This produces interference fringes in a manner similar to that in an optical interferometer. If the radio source has finite…
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sound
Constructive and destructive
…of the sum wave, while destructive interference can lead to the total cancellation of the contributing waves. An interesting example of both interference and diffraction of sound, called the “speaker and baffle” experiment, involves a small loudspeaker and a large, square wooden sheet with a circular hole in it the…
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…of the sum wave, while destructive interference can lead to the total cancellation of the contributing waves. An interesting example of both interference and diffraction of sound, called the “speaker and baffle” experiment, involves a small loudspeaker and a large, square wooden sheet with a circular hole in it the…
Read More