Domain: Natural Science — Atmospheric Science
Target concept: White light passing through a glass prism forms a fan-shaped spectrum resembling a rainbow.

Video generation prompt: A narrow beam of white light passes through a transparent triangular glass prism placed on a table, and as the prism is slowly rotated, the light is projected onto a blank wall.

Evaluation guide:
(i) Target concept: Dispersion of polychromatic white light via angular refraction in a dielectric prism.
Minimum mechanism: Light must be incident on a transparent triangular prism with non-parallel faces; material must be optically homogeneous and dispersive (e.g., crown glass); illumination must be collimated/narrow to resolve spectral separation; projection surface must be perpendicular or near-perpendicular to mean refracted ray for fan geometry to be resolvable.
(ii)Storyline: [Frame 0–2] White light beam strikes stationary prism on table → [Frame 3–5] Prism begins smooth rotation → [Frame 6–8] Spectrum fan emerges on wall, aligned with refracted beam → [Frame 9–10] Fan shifts position coherently with rotation while preserving color order and fan geometry; entire sequence viewed from fixed frontal perspective showing table, prism, light path, and wall in same continuous scene, with no cuts, no viewpoint shifts, no occlusions hiding key elements.

Manual:
Experimental Procedure
1. Place a transparent triangular glass prism flat on a table.
2. Shine a narrow beam of white light directly onto one face of the prism.
3. Slowly rotate the prism around its vertical axis while keeping it on the table.
4. Observe the changing pattern of light projected onto a blank wall opposite.
Observation of Experimental Phenomena
A fan-shaped spectrum of colors (red to violet) appears on the wall; as the prism rotates, the entire fan shifts position smoothly, maintaining its shape and color order.
Summary of Experimental Principles
White light is composed of multiple wavelengths; when passing through a prism, different wavelengths refract by different amounts, separating into a continuous visible spectrum — the rainbow-like fan shape.

Prompt Grounding rubric:
level_1: No transparent triangular prism appears; no narrow beam of light is shown; no table is present for the prism to sit on; no wall or similar flat surface is positioned to receive light from the prism; none of the setup described in the posted_prompt is present.
level_2: At least one of the prism, the light beam, or the wall is visible, but the setup is wrong in an important way: the prism is being held in a hand rather than resting on the table, no wall or projection surface is in frame, or the light is wide/diffuse rather than a narrow beam actually striking the prism.
level_3: The prism sits on the table, a narrow beam of light strikes it, and a wall or flat surface is positioned to receive whatever light exits the prism, but the prism is never shown rotating, or its rotation is so brief or ambiguous that a viewer cannot tell it turned at all.
level_4: The prism rests stably on the table and is visibly rotating through a continuous range of angles; the light beam keeps striking the prism throughout the rotation; the wall keeps receiving light from the prism the entire time, but the camera view briefly changes angle, or something momentarily blocks the table, prism, or wall from view, breaking the otherwise continuous single-scene framing.
level_5: The prism rests stably on the table for the entire clip; the narrow light beam strikes the prism continuously; the prism rotates smoothly and visibly; the wall stays in frame and keeps receiving light throughout; the camera holds one continuous, unobstructed view of the table, prism, beam path, and wall the whole time, exactly matching the setup in the posted_prompt.

Scientific and Causal Correctness rubric:
level_1: No spread of colors appears on the wall at all: the projected light stays white or goes fully dark, or the colors that do appear are scrambled (e.g., only pink and teal patches) rather than a rainbow-like sequence, or the colored patch is a round blob rather than a fan spreading out from a point.
level_2: Colors appear on the wall, but they don't behave the way dispersion should: colors show up before the beam ever reaches the prism, a colored patch is present even while the prism sits still (not rotating), only one or two colors are visible with no fan spread, or the color pattern moves in a way unrelated to which way the prism turns.
level_3: A fan-shaped patch of light forms on the wall while the prism rotates, showing at least three clearly separate colors (for instance red, green, and violet) side by side; the patch's position on the wall shifts as the prism turns, showing that the rotation is causing the shift, but the colors bleed into each other or look washed out rather than forming crisp separate bands.
level_4: The fan-shaped patch on the wall shows at least five clearly separate, correctly ordered spectral colors (a contiguous run within the red-through-violet sequence) with no colors from outside that sequence (no pink, brown, or magenta); the fan's position tracks the prism's rotation smoothly and the color order never reverses.
level_5: The wall shows the complete red-to-violet sequence as one continuous fan, every band clearly distinct from its neighbors with no blending or gaps, staying in correct red-to-violet order as it shifts smoothly across the wall in step with the prism's rotation; no color appears out of sequence, and the fan's appearance is never out of step with when the prism is actually turning.

Spatiotemporal Consistency rubric:
level_1: The prism suddenly appears in a different spot on the table with no motion connecting the two positions; the light beam blinks off and on abruptly; the wall vanishes and reappears; or the prism visibly cracks, deforms, or the table disappears mid-clip.
level_2: Several problems appear together without being as severe as full teleportation: the beam does not appear to originate from a consistent light source, the brightness of the projected patch jumps up or down abruptly with no clear cause, an obvious cut is visible partway through the clip, or the wall appears to shift in front of or behind the table in a way that breaks the scene's depth.
level_3: One small continuity slip happens: the prism's rotation looks slightly jittery for a moment, the light on the wall dims briefly and then recovers, or the beam's path looks a touch misaligned for an instant, but the prism never leaves the table, nothing disappears, and the rest of the scene stays coherent throughout.
level_4: The prism stays on the table without floating, sinking, or shifting position; the beam keeps a consistent origin and direction; the light patch stays confined to the wall without spilling past its edges or warping; the rotation is smooth and unbroken from start to finish, apart from one small flaw, such as a brief instant of motion blur on the rotating prism's edge that doesn't disrupt the rest of the scene.
level_5: The prism rotates with smooth, continuously changing angle from start to finish; the beam stays unbroken along its full path from source through the prism to the wall; the light patch glides across the wall without stutters, jumps, or warping; the table, prism, and wall keep the same physical relationship to each other and to the camera for the entire clip, with nothing appearing, vanishing, or changing shape unexpectedly.