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Interference

Part of the Optics, Waves and Modern Physics section of Coddy's Physics journey. Lesson 21 of 53.

Two waves of the same frequency: what matters is the path difference Δ.

Δ = nλ

Constructive: crest meets crest.

Δ = (n + ½)λ

Destructive: crest meets trough.

Challenge

Two waves of wavelength 0.5 m meet with a path difference of 1.5 m. How many wavelengths N is the path difference?

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Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Optics, Waves and Modern Physics

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4Mechanical Waves

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7Photons

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10Nuclear Energy

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5The Ripple Tank

Two Sources Nodal Lines How the Pattern Changes Recap - Two Speakers

8The Bohr Atom

The Bohr Model Emission and Absorption Spectral Lines Recap - Hydrogen Lamp

3Thin Lenses

Lenses and Their Rays The Lens Equation Virtual Images Two Lenses A Lens and a Mirror Recap - Build a Projector

6Light as a Wave

Light Through Two Slits Fringes on a Screen Diffraction by One Slit The Diffraction Grating Recap - Measure with a CD

9The Nucleus

Inside the Nucleus Radioactive Decay Half-Life Activity Radioactive Dating Recap - Carbon Dating