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THE VISUAL LEARNING STUDIO
See the idea. Understand the connection.
35 visual explanations across 29 chapters, with topic maps throughout the library.
The chapter index will grow as additional notes are prepared. Chapters shown here are a learning collection, not a claim that the entire exam syllabus is complete.
SEE IT. CONNECT IT. EXPLAIN IT.
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Study the expanded notes and the credited detailed textbook lessons. The current chapter index covers core topics; it is not a claim of exhaustive coverage of every examination syllabus. Check the official syllabus and primary references.
Optics — lesson overview
Reflection and refraction
Reflection has equal angles of incidence and reflection, measured from the normal. Refraction changes propagation direction when light crosses media obliquely with different refractive indices.
For the appropriate optical conditions, Snell’s law is n₁sin i = n₂sin r. Frequency stays fixed across a stationary boundary while speed and wavelength can change.
Angles measured from the surface are not the angles used directly in these laws.
Images and lenses
A real image can be formed by actual convergence of rays; a virtual image arises from apparent ray convergence. Screen formation is a useful practical distinction in ordinary ray optics.
Thin-lens equations require a consistent sign convention and paraxial approximation. Do not mix signs from different conventions.
A converging lens does not always produce a real image; an object within its focal length can produce a virtual enlarged image.
Total internal reflection
Total internal reflection requires travel from an optically denser to a rarer medium and incidence exceeding the critical angle.
At the critical angle, the refracted ray is along the boundary in the ideal model. This is different from ordinary partial reflection.
Optical fibres use guided propagation based on refractive-index structure; they do not rely on a mirror coating along every internal reflection point.
