Refraction of Light at a Water Surface

Overview

A brief visual explanation of how light bends when it passes from air into water. The animation shows the incident ray, the normal at the interface, the refracted ray, animated angle labels, and presents Snell’s law $n_1\sin\theta_1 = n_2\sin\theta_2$.

Phases

#	Phase Name	Duration	Description
1	Intro	~3s	Title fades in at the top; a horizontal line representing the air‑water interface appears.
2	Incident Ray	~5s	An incident ray from the left strikes the interface; the normal line is drawn; angle $\theta_1$ is labeled with a rotating arc.
3	Refraction	~6s	The refracted ray emerges into the water side; angle $\theta_2$ is labeled; the ray bends according to the index ratio.
4	Snell's Law	~4s	The formula $n_1\sin\theta_1 = n_2\sin\theta_2$ fades in on the right side; each term highlights as the corresponding ray/angle appears.
5	Outro	~2s	All elements fade out, leaving a brief reminder of the formula.

Layout

┌─────────────────────────────────────┐
│               TOP AREA              │
├───────────────────────┬─────────────┤
│        LEFT AREA       │ RIGHT AREA  │
│   (diagram of rays)    │ (formula)   │
├───────────────────────┴─────────────┤
│               BOTTOM AREA           │
└─────────────────────────────────────┘

Area Descriptions

Area	Content	Notes
Top	Title: “Refraction at a Water Surface”	Fades in during Intro
Left	Diagram: air‑water interface line, normal, incident ray, refracted ray, animated angle arcs $\theta_1$ and $\theta_2$	Primary visual focus
Right	Snell’s law formula $n_1\sin\theta_1 = n_2\sin\theta_2$	Appears in Phase 4, terms highlight in sync with angles
Bottom	Small caption: “$n_{air}\approx1.0,\; n_{water}\approx1.33$”	Optional, fades in with Outro

Notes

• All elements belong to a single Scene class.
• Keep total runtime under 20 seconds.
• Angle arcs should animate smoothly from 0° to the final angle.
• Use contrasting colors: air ray (red), water ray (blue), normal (gray), interface (dark line).
• No additional explanatory text is required beyond the formula and angle labels.