{
  "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": "quiz",
  "unit": {
    "slug": "alternating-current-and-electromagnetic-waves",
    "title": "交流と電磁波",
    "url": "https://manazoo.com/high/physics/alternating-current-and-electromagnetic-waves/"
  },
  "canonical_url": "https://manazoo.com/high/physics/alternating-current-and-electromagnetic-waves/quiz/",
  "questions": [
    {
      "id": "q-ac-angular-frequency-25hz",
      "type": "input",
      "prompt": "周波数25Hzの交流の角周波数ωは何rad/sか。",
      "choices": null,
      "answer": "50π",
      "accept": [
        "50π rad/s",
        "50πrad/s",
        "157rad/s"
      ],
      "explanation": "ω＝2πf＝2π×25＝50π rad/s（約157rad/s）。",
      "entities": [
        "ac-generation-and-rms-value"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-ac-average-power-peak-current-3a",
      "type": "input",
      "prompt": "最大値3.0Aの交流を20Ωの抵抗に流したとき、消費電力の時間平均は何Wか。",
      "choices": null,
      "answer": "90W",
      "accept": [
        "90"
      ],
      "explanation": "平均消費電力はP＝(1/2)I₀²R＝(1/2)×3.0²×20＝90W。",
      "entities": [
        "ac-generation-and-rms-value"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-ac-peak-vs-rms-voltage-choice",
      "type": "choice",
      "prompt": "実効値100Vの交流の最大値（瞬時値の最大）に最も近いものはどれか。",
      "choices": [
        "71V",
        "100V",
        "141V",
        "200V"
      ],
      "answer": 2,
      "accept": [],
      "explanation": "最大値V₀＝√2×実効値＝√2×100≒141V。実効値は最大値の1/√2倍になる。",
      "entities": [
        "ac-generation-and-rms-value"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-ac-period-25hz",
      "type": "input",
      "prompt": "周波数25Hzの交流の周期Tは何sか。",
      "choices": null,
      "answer": "0.04s",
      "accept": [
        "0.04",
        "0.04秒"
      ],
      "explanation": "T＝1/f＝1/25＝0.04s。",
      "entities": [
        "ac-generation-and-rms-value"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-em-frequency-from-wavelength-500nm",
      "type": "input",
      "prompt": "波長5.0×10⁻⁷m（500nm）の可視光の振動数は何Hzか。真空中の光の速さを3.0×10⁸m/sとする。",
      "choices": null,
      "answer": "6.0×10¹⁴Hz",
      "accept": [
        "6.0e14Hz",
        "6.0×10^14Hz"
      ],
      "explanation": "f＝c/λ＝3.0×10⁸/(5.0×10⁻⁷)＝6.0×10¹⁴Hz。",
      "entities": [
        "electromagnetic-wave-generation-and-properties"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-em-wave-ordering-choice",
      "type": "choice",
      "prompt": "波長の長い方から短い方へ、正しい順序で並んでいるものはどれか。",
      "choices": [
        "紫外線→可視光→赤外線→電波",
        "可視光→電波→紫外線→赤外線",
        "赤外線→電波→紫外線→可視光",
        "電波→赤外線→可視光→紫外線"
      ],
      "answer": 3,
      "accept": [],
      "explanation": "波長の長い方から、電波→赤外線→可視光→紫外線の順に並ぶ（さらに短いX線・γ線が続く）。",
      "entities": [
        "electromagnetic-wave-generation-and-properties"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-em-wave-properties-choice",
      "type": "choice",
      "prompt": "電磁波の性質として正しいものはどれか。",
      "choices": [
        "真空中は伝わらず、空気中だけを伝わる縦波である",
        "振動数が変わると真空中の速さも変わる",
        "真空中を伝わる横波で、エネルギーや情報を運ぶ",
        "磁場の変化だけで発生し、電場は関係しない"
      ],
      "answer": 2,
      "accept": [],
      "explanation": "電磁波は真空中を伝わる横波で、エネルギーや情報を運ぶことができる。",
      "entities": [
        "electromagnetic-wave-generation-and-properties"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-em-wavelength-from-frequency-100mhz",
      "type": "input",
      "prompt": "振動数1.0×10⁸Hz（100MHz）の電波の、真空中での波長は何mか。真空中の光の速さを3.0×10⁸m/sとする。",
      "choices": null,
      "answer": "3.0m",
      "accept": [
        "3m",
        "3.0"
      ],
      "explanation": "λ＝c/f＝3.0×10⁸/(1.0×10⁸)＝3.0m。",
      "entities": [
        "electromagnetic-wave-generation-and-properties"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-lc-capacitor-energy-2e-3c",
      "type": "input",
      "prompt": "電気容量500μFのコンデンサーに、電気量の最大値2.0×10⁻³Cがたまっている。コンデンサーに蓄えられる最大の静電エネルギーは何Jか。",
      "choices": null,
      "answer": "4.0×10⁻³J",
      "accept": [
        "0.004J",
        "4.0mJ"
      ],
      "explanation": "U＝Q₀²/(2C)＝(2.0×10⁻³)²/(2×500×10⁻⁶)＝4.0×10⁻³J。",
      "entities": [
        "electrical-oscillation-in-lc-circuit"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-lc-charge-at-max-current-choice",
      "type": "choice",
      "prompt": "LC回路で、コイルに流れる電流が最大になる瞬間、コンデンサーの電気量について正しいものはどれか。",
      "choices": [
        "最大である",
        "電源の電圧による",
        "0である",
        "半分である"
      ],
      "answer": 2,
      "accept": [],
      "explanation": "電流が最大のとき、エネルギーはすべて磁場エネルギーになっており、コンデンサーの電気量は0である。",
      "entities": [
        "electrical-oscillation-in-lc-circuit"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-lc-max-current-from-energy",
      "type": "input",
      "prompt": "上のエネルギーがすべて自己インダクタンス0.20Hのコイルの磁場エネルギーに移ったとき、コイルに流れる電流の最大値I₀は何Aか。",
      "choices": null,
      "answer": "0.20A",
      "accept": [
        "0.2A",
        "0.2"
      ],
      "explanation": "(1/2)LI₀²＝U より I₀＝√(2U/L)＝√(2×4.0×10⁻³/0.20)＝0.20A。",
      "entities": [
        "electrical-oscillation-in-lc-circuit"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-lc-period-09h-1000uf",
      "type": "input",
      "prompt": "自己インダクタンス0.90H・電気容量1.0×10⁻³F（1000μF）のLC回路の固有周期Tは何sか。",
      "choices": null,
      "answer": "0.06πs",
      "accept": [
        "0.06π",
        "0.06πs",
        "0.188s"
      ],
      "explanation": "T＝2π√(LC)＝2π√(0.90×1.0×10⁻³)＝2π×0.03＝0.06π s。",
      "entities": [
        "electrical-oscillation-in-lc-circuit"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-reactance-capacitor-200rad-250uf",
      "type": "input",
      "prompt": "電気容量250μFのコンデンサーに角周波数200rad/sの交流を流す。容量リアクタンスX_Cは何Ωか。",
      "choices": null,
      "answer": "20Ω",
      "accept": [
        "20"
      ],
      "explanation": "X_C＝1/(ωC)＝1/(200×250×10⁻⁶)＝20Ω。",
      "entities": [
        "reactance-of-coil-and-capacitor"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-reactance-coil-200rad-02h",
      "type": "input",
      "prompt": "自己インダクタンス0.20Hのコイルに角周波数200rad/sの交流を流す。誘導リアクタンスX_Lは何Ωか。",
      "choices": null,
      "answer": "40Ω",
      "accept": [
        "40"
      ],
      "explanation": "X_L＝ωL＝200×0.20＝40Ω。",
      "entities": [
        "reactance-of-coil-and-capacitor"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-reactance-coil-current-180v-60ohm",
      "type": "input",
      "prompt": "リアクタンス60Ωのコイルに実効値180Vの交流電源をつないだとき、電流の実効値は何Aか。",
      "choices": null,
      "answer": "3.0A",
      "accept": [
        "3.0",
        "3A"
      ],
      "explanation": "I＝V/X_L＝180/60＝3.0A。",
      "entities": [
        "reactance-of-coil-and-capacitor"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-reactance-coil-phase-choice",
      "type": "choice",
      "prompt": "コイルだけの交流回路で、電圧は電流に対してどうなるか。",
      "choices": [
        "同じ位相",
        "位相がπ/2遅れる",
        "位相がπ/2進む",
        "位相がπずれる"
      ],
      "answer": 2,
      "accept": [],
      "explanation": "コイルは電流の変化を妨げる自己誘導の起電力を生じるため、電圧は電流よりπ/2（90°）位相が進む。",
      "entities": [
        "reactance-of-coil-and-capacitor"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-rlc-impedance-80-60-120",
      "type": "input",
      "prompt": "抵抗80Ω・誘導リアクタンス60Ω・容量リアクタンス120Ωを直列につないだ回路のインピーダンスZは何Ωか。",
      "choices": null,
      "answer": "100Ω",
      "accept": [
        "100"
      ],
      "explanation": "Z＝√(R²＋(X_L－X_C)²)＝√(80²＋(60－120)²)＝√(6400＋3600)＝100Ω。",
      "entities": [
        "impedance-and-resonance-in-rlc-circuit"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-rlc-impedance-current-200v-100ohm",
      "type": "input",
      "prompt": "上の回路に実効値200Vの交流電源をつないだとき、電流の実効値は何Aか。",
      "choices": null,
      "answer": "2.0A",
      "accept": [
        "2.0",
        "2A"
      ],
      "explanation": "I＝V/Z＝200/100＝2.0A。",
      "entities": [
        "impedance-and-resonance-in-rlc-circuit"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-rlc-resonance-angular-frequency",
      "type": "input",
      "prompt": "自己インダクタンス0.40H・電気容量1.0×10⁻³F（1000μF）のコイルとコンデンサーを使ったRLC直列回路が共振する角周波数ω₀は何rad/sか。",
      "choices": null,
      "answer": "50",
      "accept": [
        "50rad/s",
        "50 rad/s"
      ],
      "explanation": "ω₀＝1/√(LC)＝1/√(0.40×1.0×10⁻³)＝50rad/s。",
      "entities": [
        "impedance-and-resonance-in-rlc-circuit"
      ],
      "verified": true,
      "placeholder": false
    },
    {
      "id": "q-rlc-resonance-impedance-choice",
      "type": "choice",
      "prompt": "RLC直列回路で共振が起きているとき、インピーダンスについて正しいものはどれか。",
      "choices": [
        "コイルのリアクタンスだけになる",
        "最大になる",
        "抵抗Rだけになり最小になる",
        "0になる"
      ],
      "answer": 2,
      "accept": [],
      "explanation": "共振ではX_LとX_Cが等しくなり打ち消し合うので、インピーダンスは最小の抵抗Rだけになる。",
      "entities": [
        "impedance-and-resonance-in-rlc-circuit"
      ],
      "verified": true,
      "placeholder": false
    }
  ]
}