Domain: Engineering — Materials Science & Engineering
Target concept: Plastic sheet undergoes melting and deformation, while the ceramic sheet shows no significant change.

Video generation prompt: White background, a ceramic plate and a plastic plate are heated simultaneously with a blowtorch to compare their heat resistance.

Evaluation guide:
(i) Target concept: Differential thermal response of materials under localized flame heating.
Minimum mechanism: A handheld blowtorch flame reaches roughly 1200–1900°C at its hottest point, far above the ~300–500°C range at which common plastics (e.g., polyethylene, polypropylene, PVC) soften, char, and decompose, so direct flame contact drives the plastic plate through softening into visible warping, bubbling, or charring rather than staying in a clean, damage-free glass-transition regime; the same flame remains far below the softening/melting point of typical ceramics (often well above 1200°C, and far higher for alumina-based ceramics), so the ceramic plate keeps its shape and rigidity throughout.
(ii)Storyline: Frame 0–1: Static wide shot showing white background, ceramic plate (light-colored, smooth, rigid), plastic plate (translucent/colored, uniform surface), and blowtorch held equidistantly. Frame 2–3: Blowtorch flame engages both plates simultaneously. Flame contact is continuous and symmetrical. Frame 4–7: Plastic plate begins progressive, irreversible shape change (visible sag/warp, possibly with localized charring or smoke); ceramic plate shows zero geometric deviation: no contour loss, no flex, no bulge, though it may pick up soot discoloration. Frame 8–9: Final state maintains side-by-side view; deformation persists in plastic; ceramic remains unchanged. Perspective: Fixed frontal viewpoint, full-frame visibility of both plates and flame base; no camera motion, no cutaways, no zooms.

Manual:
Experimental Procedure
1. Place ceramic plate and plastic plate side-by-side on white background.
2. Simultaneously apply blowtorch flame to both plates for ~3 seconds.
Observation of Experimental Phenomena
- Plastic plate undergoes visible, continuous shape deformation (warping, sagging, or edge curling).
- Ceramic plate retains original shape, flatness, and rigidity; no melting or softening observed.
Summary of Experimental Principles
Plastic sheet undergoes melting and deformation, while the ceramic sheet shows no significant change due to ceramic’s high melting point and thermal stability versus plastic’s low glass transition temperature.

Prompt Grounding rubric:
level_1: No white background present; neither ceramic plate nor plastic plate appears; no blowtorch visible; no heating action depicted.
level_2: White background present, but only one of the two plates (ceramic or plastic) appears; blowtorch is absent or not directed at either plate; no simultaneous heating action shown.
level_3: White background present; both ceramic plate and plastic plate appear side-by-side; blowtorch appears and is visibly directed toward at least one plate; however, heating is not shown occurring to both plates simultaneously: e.g., blowtorch contacts only one plate, or plates are heated in sequence.
level_4: White background present; both ceramic plate and plastic plate appear side-by-side in same scene; blowtorch appears and is visibly in contact with both plates at the same time (i.e., flame touches both plates concurrently); all objects have correct type, shape, and quantity; no extraneous objects or misplacements.
level_5: White background present; both ceramic plate and plastic plate appear side-by-side, adjacent, and fully visible; blowtorch appears with visible flame contacting both plates simultaneously; no occlusion, no object duplication, no substitution (e.g., no metal tray instead of ceramic, no foam instead of plastic), no temporal misalignment (e.g., flame appears before blowtorch is held near plates).

Scientific and Causal Correctness rubric:
level_1: No differential thermal response is depicted: neither plate shows any visible change, or the plates show a total, unambiguous reversal of expected behavior (the ceramic plate clearly softens, bubbles, sags, or loses its shape while the plastic plate remains completely rigid and unmarked throughout heating).
level_2: A partial or ambiguous single-plate reaction is shown that still points the wrong way: e.g., the ceramic plate shows a partial change (slight softening, surface bubbling, or minor edge distortion) while the plastic plate shows little or no reaction, or both plates show similar, comparably small surface changes so that no clear material-dependent contrast can be read from the scene.
level_3: Both plates are heated by the flame at the same time; the plastic plate visibly softens and deforms (e.g., sagging, warping, edge curling, or bubbling), which may include charring, browning, or smoke consistent with a polymer heated past its decomposition point; the ceramic plate keeps its flat shape and rigidity throughout, though it may show minor surface soot or discoloration from the flame that does not change its geometry; the contrast between the two plates is visible but not sharply isolated (e.g., the flame occasionally drifts toward the ceramic plate, weakening the direct comparison).
level_4: All conditions for score 3 are met, and additionally: the plastic plate's deformation is continuous and progressive (increasing sag, spreading char, or growing bubbles as heating continues) while the ceramic plate shows zero shape change (no bending, bulging, or contour loss) even if it darkens with soot; the flame is held on both plates concurrently and evenly, so the deformation-versus-no-deformation contrast is clearly attributable to the plate material rather than to uneven heating.
level_5: All conditions for score 4 are met, and additionally: the plastic plate's deformation is unambiguous and irreversible (sustained warping, melting through, or collapse under its own weight) for the full duration it is heated, while the ceramic plate shows absolutely no geometric deviation at any point; any charring, bubbling, or smoke is confined to the plastic plate and never appears on or around the ceramic plate; the causal link between flame exposure and each plate's distinct outcome is visually unambiguous from the side-by-side comparison.

Spatiotemporal Consistency rubric:
level_1: Severe spatiotemporal breakdown: the ceramic plate or plastic plate teleports or vanishes between frames; the blowtorch flame flickers in and out inconsistently with no hand or fuel-flow cause; the white background changes mid-sequence; cast shadows or highlights jump abruptly with no matching change in the flame or camera; either plate fragments or warps in a way no real material could.
level_2: Major continuity flaws: the ceramic plate or the plastic plate disappears from view and reappears without any hand, tool, or occlusion explaining it; the flame appears or vanishes without any ignition or shutoff motion; the two plates' side-by-side spacing changes abruptly (e.g., they start adjacent but end overlapping or far apart); cast shadows rotate or shift with no corresponding change in flame position or camera angle.
level_3: Minor but detectable flaws: the flame's visible tip flickers briefly (a few frames) without otherwise breaking continuity; the plates show slight positional jitter (under about 10% of a plate's width) but stay clearly recognizable and side-by-side; a hand or torch body briefly and partially occludes one plate for under a second; no plate teleports, vanishes, or swaps position with the other.
level_4: All conditions for score 3 are met, and additionally: the ceramic plate and plastic plate stay in the same spots relative to each other and to the white backdrop for the entire heating sequence; neither plate nor the flame is occluded during the deformation sequence; the flame stays visibly attached to the blowtorch tip without detaching or jumping; the torch's motion (if any) is smooth rather than jerky, and no geometric warping affects either plate's outline beyond the plastic's genuine thermal deformation.
level_5: All conditions for score 4 are met, and additionally: both plates remain fully visible and correctly positioned for the entire clip with no jitter; the flame burns continuously without flicker or gaps; no momentary occlusion of either plate or the flame occurs at any point; any operator hand motion is smooth and consistent with a fixed frontal viewpoint, and the side-by-side spatial layout between the two plates never drifts or rescales.