Domain: Engineering — Electrical Engineering
Target concept: Thermistor temperature sensors respond to warm and cold objects.

Video generation prompt: Place a thermistor connected to a battery and an LED on the desk. First, bring a cup of hot steam-containing beverage close to the thermistor, then bring a bowl of ice water close to the thermistor, and observe the change in the brightness of the LED.

Evaluation guide:
(i) Target concept: Negative Temperature Coefficient (NTC) thermistor behavior, resistance inversely proportional to temperature, causing measurable current change in a simple series circuit with LED.
Minimum mechanism: Thermistor must be NTC-type (standard for educational kits); LED brightness must be current-dependent (standard low-power indicator LED); circuit must be series-connected with no parallel bypass; ambient temperature must be stable enough for contrast to dominate.
(ii)Storyline: Frame 0–3s: Static desk shot showing thermistor-battery-LED assembly centered; cup held off-screen left. Frame 3–6s: Cup enters frame from left, approaches thermistor (steam visibly rising), LED brightness increases and holds. Frame 6–9s: Cup exits left, bowl enters from right, approaches same thermistor location (ice visible in liquid), LED brightness decreases and holds. Frame 9–10s: Bowl remains near thermistor; LED sustains dim state. Perspective: Fixed frontal desk-level view, no camera movement, full visibility of thermistor and LED throughout; no occlusion during proximity events.

Manual:
Experimental Procedure
1. Place thermistor connected to battery and LED on desk.
2. Bring cup of hot steam-containing beverage close to thermistor.
3. Bring bowl of ice water close to thermistor.
Observation of Experimental Phenomena
LED brightens when hot beverage is near thermistor; LED dims when ice water is near thermistor.
Summary of Experimental Principles
Thermistor resistance decreases with rising temperature (NTC type); increased current causes LED to brighten. Resistance increases with falling temperature; decreased current causes LED to dim.

Prompt Grounding rubric:
level_1: No thermistor, no battery, no LED, no cup of hot beverage, no bowl of ice water, or none of the listed objects appear in the video.
level_2: At least one correct object appears (e.g., LED or cup), but the full set of required objects is missing: thermistor, battery, LED, hot beverage cup, and ice water bowl are not all present; or required actions (placing, bringing close) are absent entirely.
level_3: All five core objects are present: thermistor, battery, LED, cup containing hot steam-containing beverage, and bowl containing ice water; thermistor is placed on desk with battery and LED connected; hot beverage cup is brought near thermistor at some point, and ice water bowl is brought near thermistor at some point; but sequence order is incorrect (e.g., ice water before hot beverage) or spatial relationship is broken (e.g., thermistor not visibly adjacent to either cup/bowl during proximity).
level_4: All five core objects are present and correctly identified by form/function; thermistor is visibly connected to battery and LED (wires or circuit visible); both cup and bowl are brought near the thermistor in correct sequential order (hot first, then cold); thermistor remains stationary on desk throughout; cup and bowl each approach the same side/region of thermistor; no object teleportation or disappearance, and all placements occur within a single fixed desk-level scene.
level_5: All conditions for score 4 are satisfied, and additionally: (a) thermistor is clearly distinguishable as a small cylindrical or disc-shaped electronic component (not mistaken for resistor or switch), (b) cup visibly emits steam (continuous upward vapor plume), (c) bowl visibly contains liquid with floating or submerged ice cubes, (d) LED is visibly mounted/integrated in-circuit (not held separately), (e) no extraneous objects occlude the thermistor-LED-battery assembly during either proximity event.

Scientific and Causal Correctness rubric:
level_1: LED brightness shows no change whatsoever across the entire video, or brightness changes randomly without correlation to proximity events; or LED is off throughout despite power connection.
level_2: LED brightness changes, but in wrong direction: dims when hot beverage approaches and brightens when ice water approaches; or brightness change occurs only once (not twice), or occurs without any proximity event.
level_3: LED brightness changes twice: it brightens during hot beverage proximity and dims during ice water proximity; but brightness change is not visually anchored to thermistor (e.g., LED is covered, disconnected, or changes while thermistor is not near either object); or change is discontinuous (flickers instead of smooth transition) or inconsistent with expected polarity (NTC thermistor behavior).
level_4: LED brightness increases continuously and visibly during hot beverage proximity (no flicker, no delay beyond natural response), and decreases continuously and visibly during ice water proximity; thermistor remains in direct line-of-sight between LED and viewer during both events; no contradictory brightness behavior (e.g., no simultaneous dimming during hot approach); causal link is visually supported by temporal adjacency and shared circuit context.
level_5: All conditions for score 4 are satisfied, and additionally: (a) brightness change magnitude is visibly distinct between the two events (brighter during hot, dimmer during cold; not equal change), (b) no intermediate brightness state persists after either proximity ends (LED returns to baseline pre-hot level after cold event concludes), (c) no unintended secondary brightness artifact (e.g., reflection glare mimicking brightness change).

Spatiotemporal Consistency rubric:
level_1: Thermistor, battery, or LED disappears/reappears abruptly; cup or bowl teleports between frames; lighting changes violently mid-sequence (e.g., full shadow to full spotlight); desk surface deforms or vanishes; LED or wires snap/disconnect visibly without physical cause.
level_2: One or more objects exhibit severe spatial discontinuity: e.g., thermistor shifts position >10cm between hot and cold trials without visible hand motion; cup appears fully filled then suddenly half-empty without pouring action; LED changes orientation (e.g., flips 90°) between proximity events with no rotation motion.
level_3: All objects maintain consistent location and orientation relative to desk and each other; lighting and shadows remain stable; motion is continuous (no jump cuts); however, minor inconsistencies exist: e.g., hand enters frame to place cup but never exits, or steam plume pauses/resumes unnaturally, or ice cubes visibly melt *during* the 10s without heat source, but these do not break causal perception.
level_4: All objects retain fixed spatial relationships: thermistor stays centered on desk; battery and LED remain connected and unmoved; cup and bowl approach from same horizontal plane (not one from above, one from side); steam rises continuously upward; ice remains solid and unmelted; hand motion (if shown) is smooth, unbroken, and terminates before next action begins.
level_5: All conditions for score 4 are satisfied, and additionally: (a) no inter-frame flicker or strobing in LED or steam; (b) no parallax shift indicating camera repositioning; (c) no abrupt focus change that blurs thermistor during critical proximity moments; (d) desk surface texture and reflectivity remain constant (no specular highlight jumps).