Domain: Engineering — Structural Engineering
Target concept: Effect of Height-to-Width Ratio on Lateral Stability of Structures

Video generation prompt: Two rectangular-prism paper models with different height-to-width ratios are placed side by side on a horizontal table. The left model has a height-to-width ratio of 2:1, while the right model has a ratio of 5:1. Both are subjected to the same short-duration horizontal wind load simultaneously, and the difference in their displacement distances is observed.

Evaluation guide:
(i) Target concept: Lateral stability of prismatic structures under horizontal impulse loading scales inversely with height-to-width ratio.
Minimum mechanism: Both models must behave as rigid bodies with uniform density; wind must act as a transient horizontal force at or near center of mass; table must provide fixed, frictional support; instability manifests as rigid-body rotation about a base edge, not plastic deformation or sliding.
(ii)Storyline: [Frame 0–2] Static shot: two distinct box-shaped paper models side-by-side on table, clearly differing in slenderness (left squat, right slender); [Frame 3–4] Wind onset: synchronous visual cue (e.g., air puff, particle burst) aligned horizontally toward both models’ centers; [Frame 5–8] Response phase: left model remains upright and stationary; right model begins lateral translation, then rotates about its downwind base edge; [Frame 9–10] Outcome: right model sustains tilt or rests on its side; left model unchanged. Viewpoint: fixed frontal angle showing full height and base contact of both models; no occlusion; lighting consistent and directional.

Manual:
Experimental Procedure
1. Place two identical rectangular-prism paper models side-by-side on a horizontal table.
2. Ensure left model has height-to-width ratio 2:1 (short & wide); right model has ratio 5:1 (tall & narrow).
3. Apply identical short-duration horizontal wind load simultaneously to both models.
Observation of Experimental Phenomena
The right (5:1) model undergoes greater lateral displacement and/or tilts/topples, while the left (2:1) model remains upright with minimal displacement.
Summary of Experimental Principles
A lower height-to-width ratio increases lateral stability by lowering the center of gravity and widening the base, reducing overturning moment under horizontal load.

Prompt Grounding rubric:
level_1: The scene does not show two separate box-shaped paper models with clearly different height-to-width proportions on a table: for instance only one model appears, both models look the same shape, or there's no horizontal table or wind cue at all.
level_2: Two box-shaped paper models sit on the table, but something is off: the two don't visibly differ in proportion (neither looks noticeably squatter or taller/narrower than the other), they aren't placed side by side, the wind reaches one model before the other rather than both at once, or there's no visible sign (blown debris, streamers, motion blur, particles) that wind is happening at all.
level_3: Two box-shaped paper models stand side by side on a horizontal table: the left one looks squat, short relative to its width, roughly matching a 2:1 height-to-width proportion, and the right one looks slender, tall relative to its width, roughly matching a 5:1 proportion; a wind cue (a gust, blown particles, or a fan blast) reaches both models at the same time; any visible movement of either model begins only after that wind cue starts.
level_4: All of the level-3 criteria are met, and beyond that: the camera keeps both models fully in view for the whole video, without either leaving frame or being blocked; the table and both models stay in the same relative arrangement before the wind starts; the wind cue looks the same in direction and apparent strength for both models.
level_5: All of the level-4 criteria are met, and beyond that: the two models look identical in construction apart from their height difference (same paper color and texture, same fold quality, same base footprint), so height-to-width proportion is the only visible variable; there is no visual glitch (flicker, cut, or morph) during or after the wind is applied; each model's proportions stay visually consistent with its stated ratio throughout, without either model appearing to change shape.

Scientific and Causal Correctness rubric:
level_1: The outcome contradicts the stability principle being tested: the slender 5:1 model shows less movement than the squat 2:1 model, both move by the same amount, either model starts moving before the wind cue appears, or the models crumple or flatten instead of tipping or sliding as rigid shapes.
level_2: Some displacement difference appears, but the physics doesn't add up: the squat 2:1 model moves more than the slender 5:1 model, a model moves with no wind cue visible, a model lifts straight up or spins in place instead of tipping or sliding in the wind's direction, or the models behave like cloth or liquid (sagging, bending, or crumpling) instead of rigid boxes.
level_3: The slender 5:1 model visibly shifts or moves more than the squat 2:1 model under the same wind; both models keep their box shape throughout; the movement starts only after the wind cue and continues or finishes afterward; neither model moves on its own or reverses direction; if the slender model eventually tips over, that happens only after the wind has passed, not while it is still blowing.
level_4: All of the level-3 criteria are met, and beyond that: the squat 2:1 model stays fully upright with its base flat on the table the whole time; the slender 5:1 model clearly loses its upright posture, either tilting more than 15° from vertical or falling fully onto its side; there is no in-between rocking where it wobbles and then re-settles upright, which would blur the contrast between the two models.
level_5: All of the level-4 criteria are met, and beyond that: the wind cue clearly precedes any motion in either model, and no new motion starts once the wind cue has ended, apart from the slender model continuing to fall from momentum already underway; both models keep their rigid box shape throughout, with no creasing, unfolding, or tearing; once the slender model has tipped or fallen, it does not spontaneously right itself again before the video ends.

Spatiotemporal Consistency rubric:
level_1: The scene breaks basic continuity: one or both models jump to a different spot or size between frames without visibly traveling there, one or both models flicker or dissolve rather than moving normally, the tabletop looks broken or warped, the room's lighting or shadows switch on and off abruptly, or the camera suddenly cuts to a different angle without any transition.
level_2: A model or the wind cue briefly vanishes and reappears for a frame or two; the table's edge looks unnaturally wavy or shifts slightly; the wind cue appears at a different relative spot for the left model than for the right model; the shadows the models cast change direction partway through as if the light source had moved; either model's motion looks jerky or stutters instead of flowing smoothly.
level_3: Both models and the table stay visible and recognizable throughout; the start of motion when the wind hits is a little uneven or briefly hesitates, but the overall movement still looks physically plausible; shadows stay consistent though their edges look slightly softer or harder at times; nothing vanishes from frame or reappears unexpectedly.
level_4: All of the level-3 criteria are met, and beyond that: both models stay fully visible for the entire video with no unexplained gaps; shadows keep the same direction and softness from start to finish; the camera viewpoint never moves or cuts away; the models' edges and corners stay straight and sharp rather than warping; the motion runs continuously with no freezing, skipping, or sudden jumps.
level_5: All of the level-4 criteria are met, and beyond that: the right (5:1) model's sideways shift visibly begins before it starts tipping or rotating, rather than the two happening in the wrong order; the left (2:1) model's base stays flat on the table with no perceptible lifting; the video shows no dropped or repeated frames and no sudden change in playback speed, so the whole sequence plays at one consistent pace.