Light - Reflection and Refraction · Science, chapter 9

Read the section map, ask questions about this chapter, run the concept animations, then take a quiz and see which sections to go back to.

The samjho API is not answering

Tried http://localhost:8000 — Could not reach the samjho API at http://localhost:8000.

The chapter list on this page is still real: it was read from /var/task/data/syllabus/class10.json on this machine, which ships with the repo. Asking questions and taking quizzes need the API, so those are unavailable until it is running.

Ingest state of chapter 9 is unknown

samjho could not establish whether this chapter's text has been ingested, so it will not claim either way. Could not ask the API (Could not reach the samjho API at http://localhost:8000.) Chapter detail request failed: Could not reach the samjho API at http://localhost:8000.

Sections of this chapter

Every anchor here is a citation target: a chip in an answer links straight to #section-<no>.

Take a quiz on this chapter

Ask about this chapter

Answers are built only from the passages retrieved from the ingested copy of your book for this chapter. If they do not cover your question, samjho says so instead of guessing.

Press Enter to ask. The question is sent to the samjho API with this chapter's context; it is not sent anywhere else.

Questions this chapter's sections suggest

Built from the section headings of this chapter, so they are always about something the chapter actually contains.

No questions asked in this session yet.

Concept animations for this chapter

Interactive explanations, drawn in the page — no video, no external scripts. Each one is keyboard operable, has a “what to notice” caption, and a “try this” prompt that changes what it shows.

Reflection at a plane mirror and refraction at a flat interface

conceptId: reflection-refraction

What to notice: the reflected ray always leaves at the same angle it arrived (i = r), while the refracted ray bends toward the normal on entering the denser medium and away from it on leaving — and sin i / sin r = 1.50 stays equal to the refractive index whatever the angle.

Try this: switch to glass → air, set n = 1.50 (critical angle 41.8°) and drag the angle past it — the refracted ray vanishes. Model note: the weak reflected beam is drawn at a fixed 4% of the incident light; reflectances are not computed from Fresnel’s equations.

10 further animations in the registries belong to other chapters.

Your attempts on this chapter

Checking your saved attempts…

Keyed on no id — an id created in this browser, not an account. Clearing site data clears this history.