{
  "address": "d6b4c2a5fc30dfcb32e519f7ab556bb9",
  "category": "other",
  "question": "What is 1 hp (mechanical) in W?",
  "answer": "745.700 W",
  "askedBy": {
    "kind": "guest",
    "display": "method deck",
    "stamped": false,
    "id": null
  },
  "answeredBy": "method",
  "madeAt": "2026-09-30T22:39:30.722Z",
  "validUntil": null,
  "validityClass": "forever",
  "sources": [
    {
      "label": "Guide for the Use of the International System of Units (SI)",
      "url": null
    }
  ],
  "supersedes": null,
  "supersededBy": null,
  "isSeed": false,
  "seedSource": null,
  "seedAttribution": null,
  "duplicateOfQid": null,
  "publishedAt": null,
  "unpublishedAt": null,
  "voteCount": 0,
  "queuedForSubstrate": false,
  "answerMethod": "method",
  "unsourced": false,
  "source": {
    "kind": "standard",
    "value": "NIST Special Publication 811 (2008 edition), Appendix B.8, Table for power",
    "retrieved_utc": "2026-09-30T19:29:48Z"
  },
  "qsha256": "16dc2deb336125c5fad8956dd908fd700adfc5a771c565294020ecd75dca8bb6",
  "runOne": null,
  "cardContractVersion": "card_contract/1",
  "deck_id": "method-deck",
  "deck_title": "Method Deck",
  "method": {
    "name": "Power conversion",
    "version": "1",
    "source_url_or_file": "methods/power-conversion.cjs",
    "sha256_of_method_file": "f1aabe981d27dcb49026cbc35774d727fb74f735308ecf9c94685e335d9d7f5d"
  },
  "receipt": {
    "inSubstrate": false,
    "local": true,
    "modelCallsAtMint": 0,
    "tokensAtMint": 0
  },
  "method_deck": {
    "inputs": [
      {
        "name": "value",
        "type": "number",
        "unit": "from_unit",
        "required": true,
        "description": "The power to convert"
      },
      {
        "name": "from_unit",
        "type": "string",
        "required": true,
        "description": "Unit of the input value",
        "enum": [
          "W",
          "kW",
          "hp_mech",
          "hp_metric",
          "btu_h"
        ]
      },
      {
        "name": "to_unit",
        "type": "string",
        "required": true,
        "description": "Unit to convert into",
        "enum": [
          "W",
          "kW",
          "hp_mech",
          "hp_metric",
          "btu_h"
        ]
      }
    ],
    "outputs": [
      {
        "name": "result",
        "unit": "to_unit",
        "description": "The converted power"
      }
    ],
    "steps": [
      "Look up the exact watt-equivalent of from_unit and of to_unit.",
      "Convert the input to watts: watts = value * w_per(from_unit).",
      "Convert watts to the target unit: result = watts / w_per(to_unit).",
      "Round result to 6 significant figures."
    ],
    "constants": [
      {
        "name": "W",
        "value": 1,
        "unit": "W",
        "source": 0
      },
      {
        "name": "kW",
        "value": 1000,
        "unit": "W",
        "source": 0
      },
      {
        "name": "hp_mech",
        "value": 745.6998715822702,
        "unit": "W",
        "source": 0
      },
      {
        "name": "hp_metric",
        "value": 735.49875,
        "unit": "W",
        "source": 0
      },
      {
        "name": "btu_h",
        "value": 0.2930710701722222,
        "unit": "W",
        "source": 0
      }
    ],
    "examples": [
      {
        "name": "worked example",
        "inputs": {
          "value": 1,
          "from_unit": "hp_mech",
          "to_unit": "W"
        },
        "expected": {
          "answer": "745.700 W"
        },
        "check": "By hand: 550 * 0.3048 m * (0.45359237 kg * 9.80665 m/s2) = 745.69987... W; rounded to 6 significant figures is 745.700."
      },
      {
        "name": "test vector: metric hp to watts",
        "inputs": {
          "value": 1,
          "from_unit": "hp_metric",
          "to_unit": "W"
        },
        "expected": {
          "answer": "735.499 W"
        },
        "check": "By hand: 75 kg * 9.80665 m/s2 = 735.49875 W exactly, rounded to 6 significant figures."
      },
      {
        "name": "test vector: kW to BTU/h",
        "inputs": {
          "value": 1,
          "from_unit": "kW",
          "to_unit": "btu_h"
        },
        "expected": {
          "answer": "3,412.14 BTU/h"
        },
        "check": "By hand: 1000 W / (1055.05585262/3600 W) = 3412.1416...; rounded to 6 significant figures is 3412.14."
      }
    ],
    "disclaimer": null,
    "deck_category": "units"
  },
  "status": "minted",
  "kind": "method",
  "provenanceClass": "own_question",
  "provenance": {
    "schema": "card_provenance/2.0.0",
    "chain": [
      {
        "source": {
          "kind": "standard",
          "value": "NIST Special Publication 811 (2008 edition), Appendix B.8, Table for power",
          "retrieved_utc": "2026-09-30T19:29:48Z"
        },
        "sha256": "6d08fd01dba0ba3e433ff57bebd445dafde9739c7d6f951157f04e1dd2aba2a8",
        "supersedes": null,
        "added_utc": "2026-09-30T22:39:30.722Z",
        "added_by": "method:Power conversion",
        "why": "the method that computed this answer",
        "check": null,
        "status_label": "pending",
        "signature": null
      }
    ]
  }
}