Domain: Natural Science — Physics
Target concept: Ice melted in an adiabatic bowl, demonstrating the relationship between energy input and phase change

Video generation prompt: A thermos bowl containing ice and water is placed under a continuously operating heating lamp, and observed over time.

Evaluation guide:
(i) Target concept: Latent heat absorption during solid-to-liquid phase change under constrained thermal boundary conditions.
Minimum mechanism: Thermos bowl must suppress net heat loss to environment; heating lamp must deliver directional energy input; ice must be in direct thermal contact with water; phase change must occur without bulk temperature change or secondary phase transitions (e.g., vaporization).
(ii)Storyline: Frame 0–2: Static shot showing thermos bowl centered under ON lamp, containing clearly distinguishable ice (opaque/translucent white solids) and water (transparent liquid with meniscus); ice and water coexist visibly. Frame 3–7: Progressive, continuous reduction in ice volume — top surfaces of ice fragments recede first, edges soften, fragments separate without fragmentation; water level rises steadily; no bubbles, steam, or surface agitation. Frame 8–10: Final state retains ice-water coexistence (not full melt), with visibly less ice and more water than initial; lamp remains stably illuminated; all elements remain fully visible and spatially consistent; viewpoint is fixed frontal/slightly elevated, no occlusion.

Manual:
Experimental Procedure
1. Place a thermos bowl containing both ice cubes and liquid water on a stable surface.
2. Position a heating lamp directly above the bowl, turned ON.
3. Observe continuously for 10 seconds.
Observation of Experimental Phenomena
- Ice and water coexist at start.
- Ice visibly shrinks in size over time, especially at upper surfaces facing lamp.
- Water volume increases gradually; no boiling, evaporation, or splashing occurs.
Summary of Experimental Principles
- The thermos bowl greatly reduces heat exchange with the surrounding air, so the lamp's directed heat becomes the main energy reaching the ice-water interface.
- Energy input drives solid-to-liquid phase change at a constant temperature (0 degrees C), demonstrating latent heat absorption without a rise in bulk temperature.

Prompt Grounding rubric:
level_1: None of the needed elements appear: no thermos bowl, no ice, no water, and no heating lamp show up anywhere in the video.
level_2: At least one element appears -- for instance a bowl, a lamp, or some ice -- but the setup stays incomplete or incoherent: ice and water are never shown coexisting in the bowl, the lamp never appears switched on, or the bowl and lamp are never shown together in the same frame, so the placement-then-illumination sequence described in the prompt cannot be confirmed.
level_3: A thermos bowl containing both ice and water at the same time is shown, and a lamp that is visibly emitting a light and heat glow is present in the same scene, so all three core elements -- bowl, ice-and-water, and lit lamp -- are all present, but the lamp is not positioned above the bowl, or their spatial relationship does not clearly show the lamp illuminating the bowl's contents.
level_4: All the level-3 criteria remain true, and additionally, the lamp is positioned directly above the bowl along roughly the same vertical line with nothing blocking the light path between them; the bowl stays in the same place and fully visible for the whole video; and the lamp stays visibly lit for the entire duration with no gap in illumination.
level_5: All the level-4 criteria remain true, and additionally, the bowl is roughly centered in the frame; the lamp's light reaches the bowl along a clear, unobstructed path throughout; the lamp shows no flicker or interruption in brightness; and no unrelated object ever enters the frame or blocks any part of the bowl-and-lamp setup.

Scientific and Causal Correctness rubric:
level_1: No phase change is shown: the ice stays fully solid with no size reduction, the water level never rises, and there is no visible shift between solid and liquid; or the ice disappears with no liquid water forming, or the water appears to evaporate rather than come from melted ice.
level_2: Only one phase is ever present -- either ice alone or water alone -- with no visible period where both coexist; or the melting looks instantaneous, with a piece of ice vanishing whole from one moment to the next rather than shrinking gradually.
level_3: Ice and water coexist at the start; some of the ice visibly shrinks over time while the water volume increases; however the melting looks uniform across every piece of ice with no relationship to which surfaces face the lamp, or the water's surface never visibly rises despite the ongoing heat input.
level_4: Everything required at level 3 holds, and additionally: the visible reduction in ice and the corresponding rise in water level occur together consistently; melting is noticeably faster on the ice surfaces facing the lamp than on shaded surfaces; and there is no boiling, steam, or evaporation shown at any point, nor any re-freezing.
level_5: Everything required at level 4 holds, and additionally: melting is visibly concentrated on the ice's lamp-facing, upper surfaces first, with the ice pieces shrinking unevenly (more from the top than the sides or bottom); the water volume keeps rising steadily; and there is no sudden cracking, splashing, sublimation-like disappearance, or other physically implausible behavior, such as the water appearing to freeze back or the effect reversing.

Spatiotemporal Consistency rubric:
level_1: The bowl suddenly changes position, size, or orientation between frames; the lamp appears or disappears abruptly; the ice or water flickers in or out of existence; or the lamp's light switches from off to fully on within a single frame with no gradual change.
level_2: The bowl stays roughly in place but visibly rotates or tilts; the lamp shifts sideways or up and down by a distance comparable to its own size; ice pieces jump to a new position with no visible motion connecting the two; or the water's surface height changes suddenly in a way unrelated to the melting itself.
level_3: The bowl stays fixed in position and orientation; the lamp stays fixed above the bowl; the ice and water keep a steady arrangement relative to each other inside the bowl; any change in lighting intensity happens gradually while the lamp stays on; and nothing in the scene disappears or reappears without explanation, nor does the bowl or ice show any unnatural warping.
level_4: Beyond everything required at level 3: the bowl stays centered under the lamp for the whole video; the ice pieces rest or float in the water without unexplained repositioning; the water's surface stays essentially flat aside from the natural curve where it meets the bowl wall; and the lighting's direction and softness stay the same throughout, with no jittery or warped edges on any object.
level_5: Beyond everything required at level 4: the bowl's position, the lamp's position, the shape of the remaining ice, the water level, and the lighting all change smoothly and continuously from frame to frame; there is no repeated or duplicated frame, ghosting trail, or sudden viewpoint jump; and the shadow the lamp casts stays aligned with the bowl's actual shape and position throughout.