Domain: Natural Science — Physics
Target concept: Temperature changes indicated by a liquid thermometer during heating and cooling processes

Video generation prompt: A glass liquid thermometer is placed in a beaker containing water on a hot plate, and then transferred to a second beaker containing cold water.

Evaluation guide:
(i) Target concept: Thermal expansion and contraction of liquids as a function of temperature change, measured via column displacement in a sealed capillary tube.
Minimum mechanism: Liquid must be free to expand/contract within a fixed-bore capillary; bulb must be fully immersed to ensure thermal contact; ambient pressure and gravity must remain constant; no phase change (boiling/freeze) occurs in either beaker.
(ii)Storyline: Frame 1–3: Thermometer lowered into hot-water beaker → bulb fully submerged → liquid column begins rising continuously. Frame 4–6: Thermometer lifted out, held in air briefly (no column motion), then lowered into cold-water beaker → bulb fully submerged → liquid column begins falling continuously. Frame 7–10: Column stabilizes at lower height in cold water. Perspective: Fixed frontal view, centered on thermometer and both beakers side-by-side; full thermometer always visible; bulb never occluded during immersion; no camera movement or zoom.

Manual:
Experimental Procedure
1. Place a glass liquid thermometer vertically into a beaker of water resting on a hot plate.
2. Wait briefly for liquid column to rise.
3. Remove thermometer and immediately place it vertically into a second beaker of cold water.
Observation of Experimental Phenomena
The liquid column in the thermometer rises while in hot water and falls after transfer to cold water; the change is smooth, continuous, and unidirectional in each phase.
Summary of Experimental Principles
Liquid thermometers operate on thermal expansion: the working liquid (e.g., alcohol or mercury) expands when heated and contracts when cooled, causing the column height to change proportionally to temperature.

Prompt Grounding rubric:
level_1: No beaker present; no hot plate visible; no glass liquid thermometer shown; no cold water beaker present; no sequential placement action depicted.
level_2: At least one beaker appears, and a thermometer is present, but either the hot plate is absent OR the cold water beaker is absent OR the thermometer is never placed into any beaker OR the sequence of placement (hot → cold) is not visually implied by spatial repositioning.
level_3: Two beakers are present: one on a hot plate (visibly associated with heating source), one containing visibly distinct cold water (e.g., condensation on exterior or steam absence); thermometer is fully visible and placed sequentially (first in hot-beaker, then removed and placed in cold-beaker) with clear spatial transition between locations.
level_4: All elements from score 3 are present AND thermometer remains upright and fully submerged during both placements; both beakers remain stationary and in fixed relative positions (side-by-side or adjacent within same frame); no extraneous objects obscure thermometer bulb or liquid column.
level_5: All elements from score 4 are present AND thermometer is consistently oriented (same vertical alignment), bulb fully immersed in water in both beakers, liquid column visibly continuous (no breaks or occlusions), and no frame contains both thermometer-in-hot and thermometer-in-cold simultaneously: placement actions are strictly sequential with unambiguous removal before second insertion.

Scientific and Causal Correctness rubric:
level_1: Thermometer shows no visible liquid column movement; liquid level remains static across entire video; no temperature-dependent state change (e.g., expansion/contraction) is observable; liquid color is uniform and non-responsive to environment.
level_2: Liquid column moves but direction contradicts physics: rises when moved to cold water OR falls when moved to hot water; or liquid appears solid/gel-like (no fluid meniscus); or column discontinuously jumps without motion continuity.
level_3: Liquid column visibly contracts (level drops) after transfer to cold water beaker AND expands (level rises) while in hot water beaker; contraction and expansion are unidirectional and monotonic within each phase; liquid maintains consistent color and transparency throughout.
level_4: All elements from score 3 are present AND contraction begins only after full immersion in cold water AND expansion begins only after full immersion in hot water; no reversal or pause in direction during immersion; liquid meniscus remains smooth and convex (not flat or inverted) in both conditions.
level_5: All elements from score 4 are present AND liquid column motion is continuous (no frame skips or freezes), starts moving within first visible frame of full immersion, and stops moving only after thermal equilibrium would reasonably occur (i.e., motion ceases before end of cold/hot phase); no distortion, bubbling, or separation in liquid column at any point.

Spatiotemporal Consistency rubric:
level_1: Thermometer teleports between beakers; beakers shift position or scale abruptly; lighting changes discontinuously (e.g., bright → dark with no transition); thermometer rotates or flips without physical cause; frame cuts or warping occurs.
level_2: Thermometer remains in same location while water temperature changes are implied; or beakers move independently without shared background reference; or thermometer bulb disappears behind beaker wall then reappears without occlusion logic; or shadow direction flips mid-sequence.
level_3: Thermometer moves continuously from first beaker to second; both beakers remain fixed in position and size; lighting and shadow remain consistent in direction and intensity; no object flickers, vanishes, or reappears unnaturally; motion path is physically plausible (no floating, no acceleration without cause).
level_4: All elements from score 3 are present AND thermometer orientation remains constant during transit (no rotation/tumble); occlusion is consistent (e.g., if beaker rim hides part of stem in first shot, same rim hides same portion in second shot); background elements (hot plate, table surface) remain stable and undistorted.
level_5: All elements from score 4 are present AND inter-frame motion is smooth with no strobing, judder, or ghosting; thermometer tip follows a single continuous trajectory without hesitation or micro-jumps; no parallax inconsistency between foreground (thermometer) and background (beakers, hot plate); no temporal compression/expansion (e.g., motion appears unnaturally fast/slow relative to human-scale action).