{
  "api_version": "v1",
  "publisher": {
    "name": "Manazoo",
    "url": "https://manazoo.com/"
  },
  "license": "All rights reserved（AI の参照・要約と出典リンクつきの引用は可。転載・再配布・販売は不可）",
  "terms_url": "https://manazoo.com/terms/",
  "disclaimer": "単元の並びは学習指導要領に沿って作り、年号や人物などの事実は公開データと照らし合わせています。誤りに気づいたら意見箱からお知らせください。確かめて直します。テストや受験の前には、教科書や先生の説明もあわせて確認してください。",
  "attribution": "事実データの一部は Wikidata（CC0）による。単元の構成は文部科学省「小学校学習指導要領」「中学校学習指導要領」「高等学校学習指導要領」（政府標準利用規約2.0）。",
  "kind": "entity",
  "slug": "electric-potential-and-potential-difference",
  "name": "電位と電位差",
  "entity_kind": "concept",
  "wikidata_qid": "Q55451",
  "wikidata_url": "https://www.wikidata.org/wiki/Q55451",
  "canonical_url": "https://manazoo.com/science/electric-potential-and-potential-difference/",
  "api_url": "https://manazoo.com/api/v1/entities/electric-potential-and-potential-difference.json",
  "course": {
    "slug": "physics",
    "title": "物理",
    "url": "https://manazoo.com/high/physics/"
  },
  "unit": {
    "slug": "electric-field-and-electric-potential",
    "title": "電場と電位",
    "url": "https://manazoo.com/high/physics/electric-field-and-electric-potential/"
  },
  "period": null,
  "place": null,
  "summary_points": [
    "電位V＝U/q（電荷qがもつ位置エネルギーUを電気量で割った量）。単位はV（ボルト）＝J/C。",
    "点電荷のまわりの電位はV＝kQ/r。一様な電場（強さE）では、距離dだけ離れた2点の電位差はV＝Ed。",
    "電位が等しい点を結んだ面を等電位面といい、電気力線に垂直で、電位面上を動かしても仕事は0。"
  ],
  "facts": null,
  "key_points": [
    {
      "term": "電位",
      "note": "V＝U/q（単位正電荷がもつ位置エネルギー）"
    },
    {
      "term": "点電荷の電位",
      "note": "V＝k Q / r"
    },
    {
      "term": "一様な電場の電位差",
      "note": "V＝Ed（Eは電場の強さ、dは距離）"
    },
    {
      "term": "等電位面",
      "note": "電位が等しい面。電気力線に垂直"
    }
  ],
  "summary": null,
  "causality": null,
  "timeline": [],
  "related": {
    "cause": [],
    "result": [],
    "people": [],
    "same_period_japan": []
  },
  "questions": [
    {
      "id": "q-potential-point-charge-20u-030m",
      "type": "input",
      "prompt": "2.0×10⁻⁶Cの点電荷から0.30m離れた点の電位は何Vか。",
      "choices": null,
      "answer": "6.0×10⁴",
      "accept": [
        "6.0×10⁴V",
        "60000V"
      ],
      "explanation": "V＝kQ/r＝9.0×10⁹×2.0×10⁻⁶÷0.30＝6.0×10⁴V。",
      "entities": [
        "electric-potential-and-potential-difference"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-potential-energy-from-v-and-q",
      "type": "input",
      "prompt": "電位500Vの点に4.0×10⁻⁶Cの電荷を置いたとき、電荷がもつ静電気力による位置エネルギーは何Jか。",
      "choices": null,
      "answer": "2.0×10⁻³",
      "accept": [
        "2.0×10⁻³J",
        "0.002J"
      ],
      "explanation": "U＝qV＝4.0×10⁻⁶×500＝2.0×10⁻³J。",
      "entities": [
        "electric-potential-and-potential-difference"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-potential-uniform-field-v-equals-ed",
      "type": "input",
      "prompt": "強さ1.5×10³N/Cの一様な電場の中で、電場の向きに0.040mだけ離れた2点の電位差は何Vか。",
      "choices": null,
      "answer": "60",
      "accept": [
        "60V"
      ],
      "explanation": "V＝Ed＝1.5×10³×0.040＝60V。",
      "entities": [
        "electric-potential-and-potential-difference"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-potential-uniform-field-e-from-v-d",
      "type": "input",
      "prompt": "一様な電場の中で、電場の向きに0.020m離れた2点の電位差が80Vだった。この電場の強さは何N/Cか。",
      "choices": null,
      "answer": "4000",
      "accept": [
        "4000N/C",
        "4.0×10³N/C"
      ],
      "explanation": "V＝Edより E＝V/d＝80÷0.020＝4000N/C。",
      "entities": [
        "electric-potential-and-potential-difference"
      ],
      "verified": true,
      "placeholder": false
    }
  ],
  "sources": [
    {
      "label": "文部科学省「高等学校学習指導要領（平成30年告示）解説 理科編 理数編」p.72〜73",
      "url": "https://www.mext.go.jp/content/20250311-mxt_kyoiku02-100002620_05.pdf"
    },
    {
      "label": "コトバンク「電位」（デジタル大辞泉ほか）",
      "url": "https://kotobank.jp/word/%E9%9B%BB%E4%BD%8D"
    }
  ],
  "media": [
    {
      "src": "/media/electric-potential-and-potential-difference/point-charge-potential-and-work.png",
      "alt": "正の点電荷のまわりに2つの点線の等電位面を描き、電気力線に垂直であることと、点Aから点Bへ電荷を運ぶ向きの矢印を示した図",
      "license": "オリジナル（コードで作図）",
      "author": "Asatte Studio（Manazoo）",
      "source_url": "https://manazoo.com/credits/",
      "section": "formula",
      "caption": "点電荷の電位と、電荷を運ぶ仕事"
    },
    {
      "src": "/media/electric-potential-and-potential-difference/uniform-field-v-equals-ed.png",
      "alt": "正と負に帯電した2枚の板の間に一様な電場の矢印と、電場に垂直な点線の等電位面、板の間隔dを示した図",
      "license": "オリジナル（コードで作図）",
      "author": "Asatte Studio（Manazoo）",
      "source_url": "https://manazoo.com/credits/",
      "section": "example",
      "caption": "一様な電場中の電位差V＝Ed"
    }
  ],
  "status": "published",
  "placeholder": false,
  "updated_at": "2026-10-31"
}