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task_physics__vernier_caliper__length_readout_value

Summary

  • Domain: physics
  • Scene id: vernier_caliper
  • Implementation scene: vernier_caliper
  • Implementation source: src/trace_tasks/tasks/physics/vernier_caliper/length_readout_value.py

Task Contract

Reads a length from a visible Vernier caliper by combining the main-scale position of the vernier zero with the aligned vernier tick, then selects the matching visible option letter.

Program Contract

Program: read_vernier_caliper_choice(main_scale_at_vernier_zero, aligned_vernier_tick, resolution=0.1 mm, options=visible_numeric_choices); scene=vernier_caliper; scope=length_readout_value

Candidate set: the visible caliper jaws, main scale, vernier scale, zero tick, aligned tick mark, and six visible numeric option cells inside the length_readout_value objective scope. Operands: vernier_zero_tick (semantic_role, allowed visible_vernier_zero_tick_center, source program_schema_concrete); aligned_vernier_tick (semantic_role, allowed visible_aligned_vernier_tick_center, source program_schema_concrete); main_scale_context (context_operand, allowed local_visible_main_mm_scale_near_vernier_zero, source trace_metadata); vernier_scale_context (context_operand, allowed visible_sliding_vernier_scale, source trace_metadata). Operation: evaluate read_vernier_caliper_choice over the candidate set using the visible quantities, relations, branch semantics, formulas, and visible option values encoded in the program expression; generation enforces a unique final answer. Output binding: answer uses the option_letter schema with support A through F; the selected option value equals the measured length rounded to one decimal millimeter. Annotation witnesses: one bbox witness from the finalized render. Annotation marks the selected option cell. Tick-center readout witnesses are retained in trace metadata for audit, but are not the task annotation. Query ids: single.

Reasoning Operations

Families: formula_evaluation

Query Branches

Query id Program schema
single read_vernier_caliper_choice(main_scale_at_vernier_zero, aligned_vernier_tick, resolution=0.1 mm, options=visible_numeric_choices); scene=vernier_caliper; scope=length_readout_value

Program Metadata

  • Program signatures: physics.vernier_caliper_length_readout
  • Base program contract: read_vernier_caliper_choice(main_scale_at_vernier_zero, aligned_vernier_tick, resolution=0.1 mm, options=visible_numeric_choices); scene=vernier_caliper; scope=length_readout_value
  • Parameter axes: main_mm, aligned_vernier_tick, target_readout_mm, correct_option_letter
  • Arguments:
  • vernier_zero_tick: semantic_role; allowed visible_vernier_zero_tick_center; source program_schema_concrete
  • aligned_vernier_tick: semantic_role; allowed visible_aligned_vernier_tick_center; source program_schema_concrete
  • main_scale_context: context_operand; allowed local_visible_main_mm_scale_near_vernier_zero; source trace_metadata
  • vernier_scale_context: context_operand; allowed visible_sliding_vernier_scale; source trace_metadata
  • Argument metadata status: curated
  • Supported query_ids: single

Answer Contract

  • Answer schema: option_letter
  • Answer support: A, B, C, D, E, F
  • Generator answer_gt.type: option_letter
  • The answer value is the letter of the visible option whose numeric value equals the measured length in millimeters with one decimal place.

Annotation Contract

  • Annotation schema: bbox
  • Generator annotation_gt.type: bbox
  • Annotation marks the selected visible option cell.
  • Annotation must not mark whole scale regions, derived tick points, decorative caliper casing alone, or the measured object as a substitute for the selected option cell.
  • Annotation and answer must be projected from the same generated execution trace, not inferred from pixels or prompt text.

Prompt And Trace Requirements

  • Prompt text must come from the physics Vernier-caliper v1 prompt bundle, with scene and task/query layers selected deterministically and recorded in metadata.
  • The prompt or scene must state the 0.1 mm vernier resolution so the task does not depend on hidden instrument trivia.
  • Render randomness, sampled fonts/styles, main-scale reading, aligned vernier tick, target readout, option values, correct option letter, and verifier payloads must be explicit in the instance trace.
  • Color, object fill, layout jitter, stroke width, font, and background style are non-semantic and must never determine the answer.