Domain: Engineering — Materials Science & Engineering
Target concept: Comparison of Quenching and Air Cooling Treatments for Wire and Their Bending Behavior

Video generation prompt: Heat two identical steel wires with a blowtorch until they are red-hot; quench one rapidly in clear water, while allowing the other to cool naturally in air. Then bend both wires side by side using hands or pliers.

Evaluation guide:
(i) Target concept: Differential phase transformation in steel due to cooling rate, leading to divergent mechanical behavior (brittleness vs. ductility).
Minimum mechanism: Steel must be carbon-containing (e.g., medium-carbon steel); red-hot state (>727°C) ensures austenite phase; rapid quenching suppresses diffusion, locking carbon to form martensite; slow air cooling permits diffusion, forming equilibrium ferrite-pearlite.
(ii)Storyline: [Phase 1: Heating] Both wires heated identically until cherry-red glow confirms austenitization. [Phase 2: Divergent Cooling] One wire undergoes abrupt thermal shock (water immersion → martensite); other experiences gradual convective loss (air exposure → ferrite-pearlite). [Phase 3: Mechanical Test] Post-cooling, wires retain respective microstructures, enabling immediate contrast in response to bending stress. Perspective must be fixed, frontal, and wide enough to capture both wires simultaneously during bending; full wire length and bending zone must remain continuously visible without occlusion or zoom transition.

Manual:
Experimental Procedure
1. Heat two identical steel wires with a blowtorch until both glow uniformly cherry-red.
2. Immediately quench one wire fully into clear water; leave the other suspended in open air to cool naturally.
3. After cooling, place both wires side-by-side in fixed frame and bend each using hands or pliers.
Observation of Experimental Phenomena
The quenched wire fractures abruptly (clean break or snap) when bent; the air-cooled wire bends smoothly without breaking.
Summary of Experimental Principles
Quenching forms hard, brittle martensite; air cooling forms softer, ductile ferrite-pearlite — resulting in dramatic difference in bending behavior.

Prompt Grounding rubric:
level_1: No steel wires are shown, no blowtorch or flame, no water container, and no bending action: none of the posted_prompt's required setup or steps appear.
level_2: A steel wire and a flame-like heat source appear, but there is no clear pair of two wires, no water container for quenching, no separate air-cooling context, and no side-by-side bending: most of the required setup is missing.
level_3: Two similar-looking steel wires are shown; a blowtorch-like flame is applied to both; a water container and an open-air space are both present; a bending action occurs; but the two wires are not shown together in the same frame after cooling, or the quenching and air-cooling steps are not clearly carried out as two separate, distinguishable actions on the two wires.
level_4: Two identical-looking steel wires are heated by the blowtorch until both glow red; one wire is dunked fully into the water (quenched), the other is left in open air with no contact to any liquid or container (air-cooled); both wires are then brought into the same frame and bent using hands or pliers; but either the bending tool differs between the two wires, one wire's cooled state is partly hidden during bending, or the camera framing does not keep both wires visible side by side throughout.
level_5: Two identical-looking steel wires glow a uniform red-hot color under the blowtorch; one wire is clearly and fully immersed in the water (the water surface, and any steam or splash, are visible), the other stays fully in open air with no contact to any surface or liquid; after cooling, both wires sit in the same fixed shot, arranged side by side; the same tool (hands or pliers) is used to bend each wire in turn or together, with both wires' bending response fully visible in the same shot and no part hidden from view.

Scientific and Causal Correctness rubric:
level_1: The wires never glow red-hot or show no visible heating; the quenching and air-cooling steps look identical; bending shows the same result for both wires regardless of how each was cooled.
level_2: Both wires glow red-hot, but the quenching and air-cooling steps look the same as each other (e.g., both wires are dunked, or both are simply left on the table); when bent, both wires flex the same way, with no visible difference traceable to the cooling method.
level_3: Both wires glow red-hot; one is placed in the water (quenched) and the other in open air (air-cooled); when both are bent, they show the same degree of flexibility or resistance: no visible difference in how each deforms or breaks.
level_4: Both wires glow red-hot; the quenching and air-cooling steps look clearly different from each other; after cooling, one wire bends easily (ductile) while the other resists bending or breaks; but the broken wire shows a ragged tear or crumples rather than a clean snap, or the bending wire kinks sharply at one odd spot instead of curving smoothly, suggesting uneven cooling.
level_5: Both wires glow a uniform cherry-red; the quenched wire is fully submerged in the water with visible steam or bubbling, while the air-cooled wire sits untouched in open air; after cooling, the quenched wire snaps cleanly in two with a sharp break when bent, while the air-cooled wire bends into a smooth continuous curve without cracking. Both outcomes appear in the same shot, with the cooling method clearly the visible cause of each wire's distinct bending behavior.

Spatiotemporal Consistency rubric:
level_1: Severe spatiotemporal violations: a wire vanishes and reappears in a different spot; the blowtorch or its flame appears or disappears with no ignition or shutoff shown; the water container changes size, shape, or position between frames; bending happens before the wires are ever heated; or the whole scene suddenly flashes bright or goes black with no visible cause (torch ignition, room light) to explain it.
level_2: Moderate violations: one wire disappears while being quenched and only reappears for the bending step; steam or bubbling appears in the water before the wire actually enters it; the pliers or hands change size or orientation inconsistently between the two wires; the blowtorch's flame glow suddenly jumps from one wire to the other without the torch visibly moving between them; or background objects (table, container) flicker or warp between frames.
level_3: All actions show continuous motion: the blowtorch is moved between the wires (or held steady) without ever disappearing; the flame's color and size change gradually as it heats each wire; the quenched wire is lowered into the water in one continuous motion; the air-cooled wire simply rests without ever touching a container; bending is applied via hand or pliers in one continuous grip and motion, with at most one small flaw allowed, such as a brief camera-side occlusion of one wire during the move between heating and cooling.
level_4: All elements of 3-score are present AND the flame's brightness and color change smoothly as it approaches or leaves each wire; the water surface ripples and settles naturally rather than jumping; the bending tool's grip stays continuous with no visible jump in either wire's position between consecutive frames; the wires' glow fades gradually after quenching or air-cooling rather than switching off instantly.
level_5: Zero spatiotemporal violations: every motion (torch approach, wire immersion, bending) is continuous and physically plausible; the camera never cuts or jumps; steam rises from the water only while the hot wire is in contact with it and fades once the wire cools; the torch flame flickers naturally rather than holding one frozen shape; the wires' red glow fades gradually rather than switching off at once; and the light coming from the torch flame or from the wires' own glow changes only as those sources themselves move or dim, never independently of them.