{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.friction","code":"thing-q82580","url":"https://ver.cy/models/thing/q82580/","name":"friction","alternateNames":["external friction","Skin friction drag","tidal friction","internal friction","dynamical friction","Self-locking property","atmospheric friction"],"kind":"thing","status":"published","version":"0.2.0-wave.2","language":"en","classifiers":{"family":"Thing Registry","category":"Cross-cutting context","entryKind":"thing","plane":"XCT","domain":["XCT.QLT"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"The force that resists the relative motion or tendency to motion of surfaces, layers or elements in contact, including dry friction between solids in static and kinetic forms, skin friction drag in fluids, internal friction within deforming materials, and astrophysical analogues such as tidal and dynamical friction; friction converts mechanical energy to heat, enables walking, braking and fastening through self-locking, and is reduced by lubrication and bearings.","purpose":"Let an agent explain friction and its kinds and laws, describe its role in engineering and everyday life, support calculations with coefficients, and support learning and the study of tribology.","scope":{"in":[],"out":[],"boundaries":[]},"distinguishingFeatures":["Contact force","Opposes motion","Coefficient dependent","Generates heat"],"structure":{"bundles":[{"id":"understand","name":"Understand","description":"What friction is.","layers":[{"id":"concept","name":"Concept","description":"Concept and laws.","findings":[{"id":"concept-finding","name":"Concept","description":"Concept.","questions":[{"text":"What is friction, and what do the classical laws of dry friction state about static and kinetic friction?","kind":"definition"},{"text":"Which kind of friction is meant?","kind":"boundary"}]}]},{"id":"origins","name":"Origins","description":"Physical origins.","findings":[{"id":"origins-finding","name":"Origins","description":"Origins.","questions":[{"text":"What causes friction at the microscopic level, according to tribology?","kind":"provenance"},{"text":"Which entry fits tribology?","kind":"action"}]}]}]},{"id":"calculate","name":"Calculate","description":"Calculation.","layers":[{"id":"coefficients","name":"Coefficients","description":"Coefficients.","findings":[{"id":"coefficients-finding","name":"Coefficients","description":"Coefficients.","questions":[{"text":"How is the friction force for this situation calculated from normal force and coefficient?","kind":"action"},{"text":"Which entry fits a specific material pair?","kind":"action"}]}]},{"id":"measure","name":"Measure","description":"Measuring friction.","findings":[{"id":"measure-finding","name":"Measure","description":"Measurement.","questions":[{"text":"How are friction coefficients measured?","kind":"measurement"},{"text":"Which standards apply?","kind":"provenance"}]}]}]},{"id":"apply","name":"Apply","description":"Engineering and life.","layers":[{"id":"use","name":"Use","description":"Using friction.","findings":[{"id":"use-finding","name":"Use","description":"Use.","questions":[{"text":"How do brakes, tyres, fasteners and self-locking mechanisms rely on friction?","kind":"provenance"},{"text":"Which entry fits brakes?","kind":"action"}]}]},{"id":"reduce","name":"Reduce","description":"Reducing friction.","findings":[{"id":"reduce-finding","name":"Reduce","description":"Reduction.","questions":[{"text":"How do lubrication, bearings and surface treatments reduce friction and wear?","kind":"provenance"},{"text":"Which entry fits lubrication?","kind":"action"}]}]}]},{"id":"learn","name":"Learn","description":"History and teaching.","layers":[{"id":"history","name":"History","description":"History.","findings":[{"id":"history-finding","name":"History","description":"History.","questions":[{"text":"How did the understanding of friction develop from Leonardo and Amontons to modern tribology?","kind":"provenance"},{"text":"Which references are standard?","kind":"provenance"}]}]},{"id":"teach","name":"Teach","description":"Teaching.","findings":[{"id":"teach-finding","name":"Teach","description":"Teaching.","questions":[{"text":"How can friction be taught with experiments?","kind":"action"},{"text":"Which misconceptions arise?","kind":"provenance"}]}]}]}]},"agentConduct":{"may":["Explain static and kinetic friction and drag, and cite measured coefficients with their sources.","Monitor wear, heating and grip in machines or vehicles it is authorized to observe."],"mustNot":["Present a textbook friction coefficient as valid for a real brake, tyre or floor without testing.","Advise removing lubrication or grip surfaces in a way that makes machines overheat or people slip.","Hide signs of excessive friction, such as overheating bearings, from operators.","Invent coefficients or test results."],"requiresHuman":["Approving braking, grip or slip-resistance figures used for safety."]},"ethics":{"considerations":["Too little friction causes falls and skids; too much causes wear, heat and fire.","Grip on floors and roads decides whether people are injured."],"affectedParties":["Pedestrians and drivers","Machine operators","Engineers and students"]},"owners":{"steward":"Nobody owns the phenomenon; engineers answer for the friction values they rely on.","roles":[],"masterSystems":[]},"relations":[{"target":"Q110558361","type":"parent","note":"registry parent class"},{"target":"Q2009590","type":"parent","note":"registry parent class"},{"target":"Q2916417","type":"parent","note":"registry parent class"},{"target":"Q3538122","type":"parent","note":"registry parent class"},{"target":"contact force","type":"related","note":"category"},{"target":"surface force","type":"related","note":"category"},{"target":"mechanical efficiency","type":"related","note":"losses due to friction"},{"target":"heat","type":"related","note":"energy dissipated by friction"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.friction","Wikidata: Q82580 (https://www.wikidata.org/wiki/Q82580)"]},"properties":{"applicability":"not-applicable","items":[]},"recognition":{"applicability":"optional","items":["Force resisting relative motion of surfaces","Static, kinetic, fluid, internal","Drag is fluid resistance on a body; adhesion is bonding; viscosity is internal fluid friction","Not physical; a force."]},"capabilities":{"applicability":"required","items":["explain kinds and laws","describe engineering roles","support calculations","support learning"]},"hazards":{"applicability":"required","items":["Slips and falls","Wear and overheating","Misapplied friction laws"]},"interfaces":{"applicability":"required","items":["Standards for measuring friction coefficients","Road and floor slip resistance standards","Lubricant standards"]},"context":{"applicability":"required","items":["Resistance to relative motion.","static and kinetic dry friction","rolling friction","fluid and skin friction","internal friction","tidal and dynamical friction in astrophysics"]}},"sources":[{"title":"Wikidata item Q82580: friction","url":"https://www.wikidata.org/wiki/Q82580","note":"identity and sense of the item"},{"title":"Wikipedia: Friction","url":"https://en.wikipedia.org/wiki/Friction","note":"general description of the item"}],"openQuestions":["Should tribology be a separate entry?","How should coefficient tables be linked?","How should slip resistance standards be linked?"],"resources":{"spec":"/models/things/publications/thing-q82580/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q82580/spec.json"],"providers":["Claude"],"researchStatus":"unreviewed","generatedAt":"2026-09-12T05:08:45Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"not-applicable","interaction.recognition":"filled","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"filled","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-06T19:52:02+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass","interaction.properties":"Plane XCT: no invented physical properties."},"score":1.0}}