Light and Optics
Start with the core ideas of how light travels, then move into the tools physicists use to predict what happens at boundaries, in lenses, and through optical systems. Along the way, you will see how reflection and refraction explain everyday vision, while wave effects reveal why light can create fringes, color, and fine details. The result is a practical tour of optics that connects classroom physics to real instruments and real-world phenomena.
Learning Path
Light and Optics
A clear visual overview of reflection, refraction, and the basic ideas that organize optics into geometric and wave models.
Open →Refraction & Snell's Law Explorer
Change angles and materials to see how light bends at a boundary and how Snell's law predicts the path.
Open →Geometric Optics Lab
Build ray diagrams, test image formation, and compare how mirrors and lenses shape what you see.
Open →Optics & Light
Use this quick-reference sheet to review the essential equations and vocabulary before solving problems.
- Key ideas: reflection, refraction, image formation, and the difference between ray and wave models.
- Important relationships: Snell's law, the lens equation, and the mirror equation.
- Useful for checking sign conventions, focal length, and common optics terms.
More Resources
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Common Questions
What is the difference between reflection and refraction?
Reflection is when light bounces off a surface. Refraction is when light changes speed and bends as it enters a different medium, like air into glass or water.
Why do lenses and mirrors form images?
They redirect light rays so they converge, diverge, or appear to come from a new location. That rearrangement of rays creates real or virtual images with different sizes and orientations.