Physics · Interactive learning companion

Prismatic Dispersion: Spectral Simulation

Connect refraction and dispersion without suggesting that every material has the same colour order or numerical index.

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📝 Description

Prismatic Dispersion is an optics simulation for exploring how light separates into colors through a prism. It uses physics ideas such as refraction, wavelength-dependent bending, and total internal reflection to support visual learning. It is useful for optics lessons, revision, and classroom demonstrations.

📋 Instructions

Change the available optical settings and observe how light bends and separates. Use the simulation to compare colors, paths, and dispersion effects.

🎓 Learning Guide: Prismatic Dispersion: Spectral Simulation

Learning focus: Connect refraction and dispersion without suggesting that every material has the same colour order or numerical index.

Physics Interactive learning companion

Learning objectives

Distinguish refraction of a single wavelength from separation of polychromatic light.
State why different wavelengths can leave a prism at different angles.

Concepts and principles

Snell’s law relates incidence and refraction angles at an interface: n₁sin(i)=n₂sin(r).
In normal dispersion of ordinary visible-light glasses, refractive index generally decreases as wavelength increases, so shorter wavelengths typically bend more.

Examples and worked solutions

A ray travels from air with n≈1 into glass with n=1.5 at i=30°. Estimate r.: Worked solution: sin r = sin30° / 1.5 = 1/3, hence r≈19.5°.

Try this investigation

Identify the incoming ray and refracted or dispersed output in the displayed prism.
If wavelength or material controls exist, vary one at a time and compare direction changes.
Treat any displayed indices or angles as model outputs requiring independent validation.

Expected observations and explanations

A polychromatic beam separates when the material refractive index depends on wavelength.

Assessment questions and answers

Does dispersion require that the entering light already contains multiple wavelengths?: Answer: Yes, observable colour separation requires light containing different spectral components.