src/lib/teaching/magneticEffectLessonSeeds.ts

import type { LessonSeedSourceRef, TuitionLessonSeed } from "./physicsLessonSeeds";

/**
 * Kerala SCERT Class 10 Physics — Chapter 4 "Magnetic Effect of Electric Current"
 * (chapterId phy-p1-c4, Physics Part 1, pp. 69-88). Final teaching seeds
 * (Phase 6J).
 *
 * These seeds are authored strictly from the Phase 6I source-evidence pack
 * (src/lib/teaching/source-overrides/magneticEffectEvidence.ts), which was
 * reconstructed from the extracted SCERT question bank (pp. 69-88) and figure
 * references. This chapter is qualitative at SSLC level: it has rules (right-hand
 * thumb rule, solenoid polarity, force direction) but no numerical equations, so
 * `formulas` is intentionally empty and the rules are taught in the teach/board
 * steps. Content is short + teacher-style; no PYQ claims, no guarantee language.
 *
 * The previously flagged circular-coil/solenoid and force-direction missions
 * are now source-backed by the extracted SCERT text: pp. 73, 75, 77, 79, 80,
 * 81 and the assessment prompt on p. 85.
 */

const CHAPTER_ID = "phy-p1-c4";
const CHAPTER_TITLE = "Magnetic Effect of Electric Current";

const MAGNETIC_SOURCE: LessonSeedSourceRef = {
  label: "Kerala SSLC Physics — Magnetic Effect of Electric Current (pp. 69-88)",
  sourceBook: "Kerala SCERT Physics, Standard X (2025)",
  chapterTitle: CHAPTER_TITLE,
  pageRange: "69-88",
  url: null,
  confidence: "source_backed",
};

function magneticSeed(seed: Omit<TuitionLessonSeed, "chapterId" | "subject" | "chapterTitle">): TuitionLessonSeed {
  return { ...seed, chapterId: CHAPTER_ID, subject: "Physics", chapterTitle: CHAPTER_TITLE };
}

/** Traceability: which Phase 6I evidence ids back each mission. */
export const MAGNETIC_EFFECT_MISSION_EVIDENCE: Record<string, string[]> = {
  M1: ["def-magnetic-effect-current", "def-magnetic-field-lines", "dia-oersted-setup", "act-oersted", "q-field-direction-ab"],
  M2: ["rule-right-hand-thumb", "dia-right-hand-thumb", "q-find-field-direction"],
  M3: ["def-solenoid", "rule-solenoid-polarity", "dia-solenoid-field", "act-solenoid", "q-solenoid-polarity", "act-circular-coil"],
  M4: ["def-electromagnet", "rule-electromagnet-strength", "dia-electromagnet", "q-increase-coil-strength"],
  M5: ["q-electromagnet-applications", "dia-electromagnet"],
  M6: ["def-force-on-conductor", "rule-force-direction", "dia-force-on-conductor", "act-force-on-conductor", "q-force-factors"],
  M7: ["def-electric-motor", "dia-electric-motor", "act-electric-motor", "q-motor-working", "q-commutator-need"],
  M8: ["dia-loudspeaker", "q-loudspeaker-energy"],
  M9: ["q-motor-working", "q-commutator-need", "q-electromagnet-applications", "q-force-factors"],
  M10: ["rule-right-hand-thumb", "rule-solenoid-polarity", "rule-electromagnet-strength", "def-electric-motor"],
};

// M1 — Magnetic Field Around a Current-Carrying Conductor
const M1: TuitionLessonSeed = magneticSeed({
  missionId: "M1",
  missionTitle: "Magnetic Field Around a Current-Carrying Conductor",
  goal: "Show that a current-carrying conductor produces a magnetic field, and that its direction depends on the current direction.",
  estimatedMinutes: 30,
  contentType: "concept",
  tags: ["magnetic effect", "magnetic field", "field lines", "Oersted", "current direction"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "A compass sits still near a wire with no current. What do you think happens to the needle when you switch the current on?",
    expectedPoints: ["The needle deflects", "So the current must create a magnetic field"],
    misconceptionCheck: "Students think only permanent magnets make magnetic fields — a current does too.",
  },
  teach: {
    teacherIntro: "Imagine a coconut tree in the wind. Its branches sway. Now, imagine a tiny current flowing through a wire (like a thin coconut branch). The surrounding air (like the air around the coconut tree) starts moving. We see this air movement because a small magnet nearby (like a leaf on the coconut tree) starts to sway.",
    explanationBlocks: [
      {
        heading: "Current produces a magnetic field",
        explanation: "Place a magnetic needle near a straight conductor. When the current is switched on, the needle deflects — the current has made a magnetic field around the conductor.",
        keyTerms: ["magnetic effect of current", "magnetic needle"],
      },
      {
        heading: "Field lines are concentric circles",
        explanation: "Around a straight current-carrying conductor the magnetic field lines form concentric circles centred on the wire.",
        keyTerms: ["magnetic field lines", "concentric circles"],
      },
      {
        heading: "Direction depends on current direction",
        explanation: "If the current direction is reversed, the needle deflects the opposite way — the direction of the field reverses with the current.",
        keyTerms: ["current direction", "field reverses"],
      },
    ],
    analogy: "The wire is like a stone dropped in water — the ripples (field lines) spread out as circles around it.",
    malayalamSupport: "ചാലകത്തിലൂടെ വൈദ്യുതി ഒഴുകുമ്പോൾ ചുറ്റും കാന്തികക്ഷേത്രം ഉണ്ടാകുന്നു; കാന്തസൂചി വ്യതിചലിക്കുന്നു. വൈദ്യുതിയുടെ ദിശ മാറ്റിയാൽ ക്ഷേത്രത്തിന്റെ ദിശയും മാറും.",
    manglishSupport: "Current ozhukumbol conductor-inu chuttum magnetic field undaakum; compass needle deflect aakum. Current direction maattiyaal field direction-um maarum.",
  },
  visualBoard: {
    boardTitle: "Current makes a magnetic field",
    frames: [
      {
        id: "m1-f1",
        title: "Oersted's experiment",
        teacherAction: "Draw a wire over a compass, connected to a cell and switch; show the needle deflecting when the switch is on.",
        boardText: ["Switch ON → needle deflects", "Current → magnetic field around the wire"],
        diagramDescription: "Straight conductor over a magnetic compass; cell and switch; deflected needle.",
        imageUrl: "assets/textbook-figures/img_page68_idx2.png",
        studentFocus: "Current alone creates a magnetic field.",
      },
      {
        id: "m1-f2",
        title: "Concentric field lines",
        teacherAction: "Draw the straight wire with concentric circles around it.",
        boardText: ["Field lines = concentric circles", "Reverse current → field reverses"],
        diagramDescription: "Straight wire with concentric circular field lines; arrows flip when current flips.",
        imageUrl: "assets/textbook-figures/img_page69_idx3.png",
        studentFocus: "Straight conductor → circular field lines.",
      },
    ],
  },
  docDoeTrick: {
    title: "Current ON → Compass turns",
    trick: "No current, still needle. Current on, needle turns. Reverse current, needle turns the other way.",
    whyItWorks: "It ties the magnetic effect to the one thing you can see — the compass deflection and how it follows the current.",
  },
  keyNotes: [
          "A wire with current (like a coconut branch) creates a magnetic field around it (like the moving air).",
          "We see this magnetic field because a small magnet nearby (like a leaf) starts to move.",
          "Think of a straight wire like a football field. The magnetic field lines are like soccer balls going around in circles.",
          "If we change the direction of the current (like a change in the ball's direction), the magnetic field lines change direction too (like the soccer ball moving in a new direction).",
          "No current means no magnetic field around the wire (like a still football field)."
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 2,
      question: "What is observed when a magnetic needle is placed near a straight conductor and current is passed through it?",
      answerPoints: ["The magnetic needle deflects, showing a magnetic field is produced around the conductor.", "When the current direction is reversed, the needle deflects in the opposite direction."],
      keywords: ["magnetic needle", "deflects", "magnetic field", "current direction"],
      commonMistakes: ["Saying nothing happens", "Not mentioning that reversing the current reverses the deflection"],
      boardStyleRewrite: "When current flows, the magnetic needle deflects, showing that a magnetic field is produced around the conductor. Reversing the current reverses the direction of deflection.",
    },
  ],
  yourTurn: {
    prompt: "What is the shape of the magnetic field lines around a straight current-carrying conductor? (2 marks)",
    expectedAnswerPoints: ["They are concentric circles", "Centred on the conductor"],
    hint: "Think about the ripples around a wire.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "States the field lines are circles/concentric circles", marks: 1, requiredKeywords: ["circle"] },
      { point: "States they are centred on / around the conductor", marks: 1, requiredKeywords: ["conductor", "around"] },
    ],
    commonMissingParts: ["The word 'concentric'", "That the circles are around the conductor"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m1-q1",
      type: "mcq",
      question: "When current flows through a straight conductor, the magnetic field lines around it are",
      options: ["straight lines", "concentric circles", "ellipses", "no field forms"],
      answer: "concentric circles",
      explanation: "Around a straight current-carrying conductor the field lines are concentric circles.",
      difficulty: "easy",
      tags: ["field lines"],
    },
    {
      id: "m1-q2",
      type: "short",
      question: "What happens to the magnetic needle if the direction of the current is reversed?",
      answer: "It deflects in the opposite direction.",
      explanation: "The field direction reverses with the current, so the needle deflects the other way.",
      difficulty: "medium",
      tags: ["current direction"],
    },
  ],
  recap: {
    summary: [
              "Current creates a magnetic field.",
              "Straight wire → magnetic field lines are like concentric circles.",
              "Reverse current → reverse magnetic field."
            ],
    mustRemember: ["Oersted: current deflects a compass", "Field direction follows current direction"],
  },
  revisionSave: {
    flashcards: [
      { front: "What did Oersted's experiment show?", back: "A current-carrying conductor produces a magnetic field." },
      { front: "Field line shape around a straight wire?", back: "Concentric circles." },
      { front: "Reverse the current — what happens to the field?", back: "Its direction reverses." },
    ],
    revisionNotes: ["Current → magnetic field (compass deflects)", "Straight wire → circular field lines"],
    weakAreaTags: ["magnetic effect", "magnetic field around conductor"],
  },
  qualityFlags: { needsHumanReview: false },
});

// M2 — Right-Hand Thumb Rule
const M2: TuitionLessonSeed = magneticSeed({
  missionId: "M2",
  missionTitle: "Right-Hand Thumb Rule",
  goal: "Apply the right-hand thumb rule to find the direction of the magnetic field around a straight conductor.",
  estimatedMinutes: 25,
  contentType: "diagram",
  tags: ["right-hand thumb rule", "field direction", "current", "rule"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "You know a current makes a circular field around a wire. How do you decide which way the field points?",
    expectedPoints: ["Use a rule with your hand", "The right-hand thumb rule"],
    misconceptionCheck: "Students grab the wire with the left hand, or point the thumb along the field instead of the current.",
  },
  teach: {
    teacherIntro: "Imagine you're holding a cup of coffee on a rainy day. The rain is like the current in a conductor. Now, hold it with your right hand, just like you hold your coffee. Your thumb will point in the direction of the rain, or the current. Your curled fingers will show you the direction of the magnetic field around your conductor. Remember, only your right hand, thumb for the current, and curled fingers for the field!",
    explanationBlocks: [
      {
        heading: "How to hold your hand",
        explanation: "Grip the conductor with your right hand so that the thumb points along the direction of the current.",
        keyTerms: ["right hand", "thumb = current"],
      },
      {
        heading: "Read the field",
        explanation: "The way the curled fingers wrap around the conductor is the direction of the magnetic field lines.",
        keyTerms: ["curled fingers", "field direction"],
      },
      {
        heading: "Apply it step by step",
        explanation: "1) Note the current direction. 2) Point the right thumb that way. 3) The curl of the fingers gives the field direction.",
        keyTerms: ["step by step"],
      },
    ],
    analogy: "Like opening a tap: your thumb points the way water flows (current), your fingers curl the way the handle turns (field).",
    malayalamSupport: "വലതു കൈ പെരുവിരൽ വൈദ്യുതിയുടെ ദിശയിൽ; വളഞ്ഞ വിരലുകൾ കാന്തികക്ഷേത്രത്തിന്റെ ദിശ കാണിക്കുന്നു. ഇടതു കൈ ഉപയോഗിക്കരുത്.",
    manglishSupport: "Valathu kai perуviral current direction-il; valanja viralukal field direction kaanikkum. Left hand upayogikkaruthu.",
  },
  visualBoard: {
    boardTitle: "Right-hand thumb rule",
    frames: [
      {
        id: "m2-f1",
        title: "Thumb = current",
        teacherAction: "Draw a right hand gripping a vertical wire, thumb pointing up along the current.",
        boardText: ["Right hand grips the wire", "Thumb → current direction"],
        diagramDescription: "Right hand around a conductor, thumb along the current.",
        imageUrl: "assets/textbook-figures/img_page70_idx1.png",
        studentFocus: "Thumb always points along the current.",
      },
      {
        id: "m2-f2",
        title: "Fingers = field",
        teacherAction: "Show the curled fingers as the circular field lines around the wire.",
        boardText: ["Curled fingers → field direction", "Never use the left hand"],
        diagramDescription: "Curled fingers wrapping the wire, matching the concentric field circles.",
        imageUrl: "assets/textbook-figures/img_page71_idx1.png",
        studentFocus: "The curl of the fingers is the field.",
      },
    ],
  },
  docDoeTrick: {
    title: "Thumb current, fingers field",
    trick: "Right hand only: Thumb = current, curled Fingers = field.",
    whyItWorks: "Two words fixed to the two fingers stop the most common mix-ups under exam pressure.",
  },
  keyNotes: [
          "The right-hand thumb rule helps us find the magnetic field direction.",
          "Hold the conductor with your right hand, like holding a football.",
          "Point your thumb in the direction of the current, like it's flowing through a pipe.",
          "Your curled fingers will show you the direction of the magnetic field lines.",
          "Don't make the mistake of using your left hand or pointing your thumb in the wrong direction!"
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 2,
      question: "State the right-hand thumb rule.",
      answerPoints: ["Grip the conductor with the right hand so the thumb points along the current.", "The curled fingers then give the direction of the magnetic field lines."],
      keywords: ["right hand", "thumb", "current", "curled fingers", "field"],
      commonMistakes: ["Using the left hand", "Swapping thumb and fingers"],
      boardStyleRewrite: "If a current-carrying conductor is held in the right hand with the thumb pointing along the current, the curled fingers give the direction of the magnetic field around it.",
    },
  ],
  yourTurn: {
    prompt: "A student uses the left hand to apply the thumb rule. What is wrong and how do you correct it? (2 marks)",
    expectedAnswerPoints: ["The rule uses the right hand, not the left", "Right thumb along current, curled fingers give the field"],
    hint: "Which hand, and what does each part show?",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "Identifies that the right hand must be used", marks: 1, requiredKeywords: ["right hand"] },
      { point: "States thumb = current, fingers = field", marks: 1, requiredKeywords: ["thumb", "field"] },
    ],
    commonMissingParts: ["Naming the right hand", "The thumb/finger meanings"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m2-q1",
      type: "mcq",
      question: "In the right-hand thumb rule, the thumb points along the",
      options: ["magnetic field", "current", "force", "north pole"],
      answer: "current",
      explanation: "The thumb points along the current; the curled fingers give the field.",
      difficulty: "easy",
      tags: ["right-hand thumb rule"],
    },
    {
      id: "m2-q2",
      type: "short",
      question: "In the right-hand thumb rule, what do the curled fingers represent?",
      answer: "The direction of the magnetic field lines.",
      explanation: "The curl of the fingers around the conductor is the field direction.",
      difficulty: "medium",
      tags: ["field direction"],
    },
  ],
  recap: {
    summary: [
              "Don't forget, use only your right hand!",
              "Thumb points in the direction of the current, like a flowing river.",
              "Curled fingers show the direction of the magnetic field lines, like the way rain falls in the monsoon."
            ],
    mustRemember: ["Never the left hand", "Thumb current, fingers field"],
  },
  revisionSave: {
    flashcards: [
      { front: "Which hand for the thumb rule?", back: "The right hand." },
      { front: "Thumb points along…?", back: "The current." },
      { front: "Curled fingers show…?", back: "The magnetic field direction." },
    ],
    revisionNotes: ["Right-hand thumb rule: thumb=current, fingers=field", "Left hand is the common trap"],
    weakAreaTags: ["right-hand thumb rule", "field direction"],
  },
  splitScreen: {
    left: { title: "Straight Conductor", imageUrl: "assets/textbook-figures/img_page70_idx1.png", caption: "Magnetic field lines are concentric circles.", captionHighlight: "Right Hand Thumb Rule" },
    right: { title: "Circular Loop", imageUrl: "assets/textbook-figures/img_page71_idx1.png", caption: "Field lines are straight at the centre.", captionHighlight: "Max strength at centre" }
  },
  qualityFlags: { needsHumanReview: false },
});

// M3 — Circular Coil and Solenoid
const M3: TuitionLessonSeed = magneticSeed({
  missionId: "M3",
  missionTitle: "Magnetic Field of a Circular Coil and a Solenoid",
  goal: "Describe the magnetic field of a circular coil and a solenoid, and find a solenoid's polarity.",
  estimatedMinutes: 30,
  contentType: "diagram",
  tags: ["circular coil", "solenoid", "field pattern", "polarity", "bar magnet"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "A straight wire gives circular field lines. What do you think the field looks like if the wire is wound into a coil?",
    expectedPoints: ["The field of each turn adds up", "It starts to look like a bar magnet"],
    misconceptionCheck: "Students expect a coil's field to still be simple circles — wound turns combine into a bar-magnet-like field.",
  },
  teach: {
    teacherIntro: "Kerala rains bring water to the coconut fields. A long coil (like a big rope) keeps the magnetic field close. It behaves like a big magnet bar!",
    explanationBlocks: [
      {
        heading: "Circular coil (textbook activity)",
        explanation: "In the textbook activity, a circular coil produces flux lines that go inward when current is clockwise and outward when current is anticlockwise.",
        keyTerms: ["circular coil", "faces of the coil"],
      },
      {
        heading: "Solenoid behaves like a bar magnet",
        explanation: "A solenoid is a long coil of many turns. Its field pattern is like that of a bar magnet, with a north pole at one end and a south pole at the other.",
        keyTerms: ["solenoid", "bar magnet", "poles"],
      },
      {
        heading: "Finding the polarity",
        explanation: "Curl the right-hand fingers along the current in the turns; the thumb points to the north pole. At an end where the current looks anticlockwise you see the north pole; clockwise shows the south pole.",
        keyTerms: ["polarity", "clockwise", "anticlockwise"],
      },
    ],
    analogy: "Each turn of the coil is a small ring magnet; stacking many turns makes one strong bar magnet.",
    malayalamSupport: "സോളിനോയ്ഡ് ബാർ കാന്തം പോലെ പ്രവർത്തിക്കുന്നു — ഒരറ്റം നോർത്ത്, മറ്റേ അറ്റം സൗത്ത്. വൈദ്യുതി anticlockwise കാണുന്ന അറ്റം നോർത്ത് പോൾ.",
    manglishSupport: "Solenoid bar magnet pole aakum — oru attam north, mattethu south. Current anticlockwise kaanunna attam north pole.",
  },
  visualBoard: {
    boardTitle: "Coil and solenoid fields",
    frames: [
      {
        id: "m3-f1",
        title: "Solenoid = bar magnet",
        teacherAction: "Draw a solenoid as a row of loops with field lines through the axis, and mark N and S ends.",
        boardText: ["Solenoid field ≈ bar magnet field", "One end N, other end S"],
        diagramDescription: "Helical coil with axial field lines; N and S marked at the ends.",
        imageUrl: "assets/textbook-figures/img_page74_idx3.png",
        studentFocus: "A solenoid acts like a bar magnet.",
      },
      {
        id: "m3-f2",
        title: "Polarity from current",
        teacherAction: "At each end, draw the current arrows; anticlockwise = north, clockwise = south.",
        boardText: ["Anticlockwise end → North pole", "Clockwise end → South pole"],
        diagramDescription: "Two coil ends showing current direction and the resulting pole.",
        imageUrl: "assets/textbook-figures/img_page74_idx4.png",
        studentFocus: "Curl fingers along current → thumb to north.",
      },
    ],
  },
  docDoeTrick: {
    title: "A-N / C-S ends",
    trick: "Anticlockwise end = North, Clockwise end = South.",
    whyItWorks: "It converts the right-hand rule into a two-line check you can do straight from the diagram.",
  },
  // Day 20 — restored from the SCERT-verified wording. A pedagogy rewrite had
  // replaced these with confusing analogies AND a reversed polarity rule
  // ("clockwise = north") that contradicted this seed's own A-N/C-S trick and
  // the right-hand rule — a real physics error caught by the seed tests.
  keyNotes: [
    "In the textbook coil activity, clockwise current gives inward flux lines; anticlockwise current gives outward flux lines.",
    "A solenoid is a long coil of many turns of insulated wire.",
    "A current-carrying solenoid behaves like a bar magnet, with a north pole at one end and a south pole at the other.",
    "The end where the current appears anticlockwise is the North pole; the end where it appears clockwise is the South pole.",
  ],
  formulas: [],
  examAnswers: [
    {
      marks: 2,
      question: "How is a current-carrying solenoid similar to a bar magnet?",
      answerPoints: ["Its magnetic field pattern is like that of a bar magnet.", "It has a north pole at one end and a south pole at the other."],
      keywords: ["solenoid", "bar magnet", "north pole", "south pole"],
      commonMistakes: ["Saying the field is just circles", "Not mentioning the two poles"],
      boardStyleRewrite: "A current-carrying solenoid has a magnetic field like a bar magnet, with a north pole at one end and a south pole at the other.",
    },
  ],
  yourTurn: {
    prompt: "At one end of a solenoid the current appears clockwise. What is the polarity of that end? (2 marks)",
    expectedAnswerPoints: ["That end is a south pole", "Anticlockwise would be a north pole"],
    hint: "Clockwise vs anticlockwise decides the pole.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "States the clockwise end is a south pole", marks: 1, requiredKeywords: ["south"] },
      { point: "Links polarity to current direction (clockwise/anticlockwise)", marks: 1, requiredKeywords: ["clockwise"] },
    ],
    commonMissingParts: ["Naming the south pole", "Linking it to the current direction"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m3-q1",
      type: "mcq",
      question: "A current-carrying solenoid behaves like a",
      options: ["single wire", "bar magnet", "resistor", "capacitor"],
      answer: "bar magnet",
      explanation: "Its field pattern is like a bar magnet, with N and S ends.",
      difficulty: "easy",
      tags: ["solenoid"],
    },
    {
      id: "m3-q2",
      type: "short",
      question: "At the end of a solenoid where the current is anticlockwise, which pole is seen?",
      answer: "The north pole.",
      explanation: "Curl the right-hand fingers along the current; the thumb (north) points out of the anticlockwise end.",
      difficulty: "exam",
      tags: ["polarity"],
    },
  ],
  recap: {
    summary: [
              "Coil keeps the field close",
              "Solenoid behaves like a big magnet bar",
              "Anticlockwise = N, clockwise = S"
            ],
    mustRemember: ["Solenoid = bar magnet", "Read polarity from the current direction"],
  },
  revisionSave: {
    flashcards: [
      { front: "A solenoid behaves like…?", back: "A bar magnet (N and S ends)." },
      { front: "Anticlockwise current end = ?", back: "North pole." },
      { front: "Clockwise current end = ?", back: "South pole." },
    ],
    revisionNotes: ["Solenoid = bar magnet", "Polarity from current: A→N, C→S"],
    weakAreaTags: ["solenoid", "field pattern"],
  },
  qualityFlags: { needsHumanReview: false },
});

// M4 — Electromagnet and Factors Affecting Its Strength
const M4: TuitionLessonSeed = magneticSeed({
  missionId: "M4",
  missionTitle: "Electromagnet and Factors Affecting Its Strength",
  goal: "Explain what an electromagnet is and list the factors that make it stronger.",
  estimatedMinutes: 30,
  contentType: "concept",
  tags: ["electromagnet", "soft-iron core", "number of turns", "current", "temporary magnet"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "A solenoid acts like a magnet only while current flows. How could we make that magnet much stronger?",
    expectedPoints: ["Add a soft-iron core", "Increase the turns or the current"],
    misconceptionCheck: "Students think an electromagnet is permanent — it is a magnet only while current flows.",
  },
  teach: {
    teacherIntro: "Imagine you have a coconut tree. When you connect a wire to the coconut tree, it becomes a strong magnet. But when you remove the wire, the magnet is gone! An electromagnet is like that coconut tree. It's a magnet only when there's a flow of electricity, and it loses its magnetism when the electricity stops.",
    explanationBlocks: [
      {
        heading: "What an electromagnet is",
        explanation: "Wind a coil around a soft-iron core and pass current: the core becomes a strong temporary magnet. Switch off the current and it stops being a magnet.",
        keyTerms: ["electromagnet", "soft-iron core", "temporary magnet"],
      },
      {
        heading: "Factors that increase the strength",
        explanation: "The strength increases with (1) the number of turns of the coil, (2) the current through the coil, and (3) using a soft-iron core.",
        keyTerms: ["number of turns", "current", "core material"],
      },
      {
        heading: "Why 'temporary'",
        explanation: "Soft iron loses its magnetism quickly when the current is switched off, so the electromagnet can be turned on and off.",
        keyTerms: ["temporary magnet", "switch on/off"],
      },
    ],
    analogy: "The coil is the muscle and the soft-iron core is the barbell — together they lift far more than the coil alone.",
    malayalamSupport: "വൈദ്യുതകാന്തം = കോയിൽ + മൃദു-ഇരുമ്പ് കാമ്പ്; വൈദ്യുതി ഉള്ളപ്പോൾ മാത്രം കാന്തം. ശക്തി കൂട്ടാൻ: ചുറ്റുകളുടെ എണ്ണം, വൈദ്യുതി, ഇരുമ്പ് കാമ്പ്.",
    manglishSupport: "Electromagnet = coil + soft iron core; current ullappol maathram magnet. Strength koottaan: number of turns, current, iron core.",
  },
  visualBoard: {
    boardTitle: "Electromagnet and its strength",
    frames: [
      {
        id: "m4-f1",
        title: "Coil on a soft-iron core",
        teacherAction: "Draw a soft-iron core with a coil wound on it, connected to a cell; show it lifting iron pieces.",
        boardText: ["Coil + soft-iron core", "Current ON → lifts iron; OFF → drops it"],
        diagramDescription: "Soft-iron core with a coil, cell, and iron pieces attracted when current flows.",
        imageUrl: "assets/textbook-figures/img_page74_idx5.png",
        studentFocus: "Magnet only while current flows.",
      },
      {
        id: "m4-f2",
        title: "Strength factors",
        teacherAction: "List the three factors that make it stronger.",
        boardText: ["More turns", "More current", "Soft-iron core"],
        studentFocus: "Three ways to make it stronger.",
      },
    ],
  },
  docDoeTrick: {
    title: "Turns-Current-Core",
    trick: "To make it stronger: more Turns, more Current, a soft-iron Core.",
    whyItWorks: "Three anchor words are exactly the three marks in a strength-factor answer.",
  },
  keyNotes: [
          "An electromagnet is a coil with a soft-iron core.",
          "It is a magnet only while current flows (like a temporary magnet).",
          "More turns in the coil make the magnet stronger (like adding more layers to a football goal post).",
          "More electricity flowing through the coil makes the magnet stronger (like adding more fuel to an auto rickshaw engine).",
          "A soft-iron core helps the electromagnet become much stronger (like cooking rice with a good pot)."
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 3,
      question: "State three factors that affect the strength of an electromagnet.",
      answerPoints: ["The number of turns of the coil.", "The current flowing through the coil.", "The use of a soft-iron core."],
      keywords: ["number of turns", "current", "soft-iron core"],
      commonMistakes: ["Listing only the current", "Forgetting the soft-iron core"],
      boardStyleRewrite: "The strength of an electromagnet increases with the number of turns of the coil, the current through it, and by using a soft-iron core.",
    },
  ],
  yourTurn: {
    prompt: "Why is an electromagnet called a temporary magnet? (2 marks)",
    expectedAnswerPoints: ["It is a magnet only while current flows", "It loses magnetism when the current is switched off"],
    hint: "Think about what happens when you switch off the current.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "Magnet only while current flows", marks: 1, requiredKeywords: ["current", "flows"] },
      { point: "Loses magnetism when current is off", marks: 1, requiredKeywords: ["off", "loses"] },
    ],
    commonMissingParts: ["That it needs current to be a magnet", "That it loses magnetism when off"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m4-q1",
      type: "mcq",
      question: "Which core makes the strongest electromagnet?",
      options: ["wood", "soft iron", "plastic", "copper"],
      answer: "soft iron",
      explanation: "A soft-iron core greatly increases the electromagnet's strength.",
      difficulty: "easy",
      tags: ["soft-iron core"],
    },
    {
      id: "m4-q2",
      type: "short",
      question: "Name two ways to increase the strength of an electromagnet apart from the core.",
      answer: "Increase the number of turns and increase the current.",
      explanation: "More turns and more current both increase the magnetic strength.",
      difficulty: "medium",
      tags: ["number of turns", "current"],
    },
  ],
  recap: {
    summary: [
              "An electromagnet is a coil with a soft-iron core.",
              "It's a magnet only when there's electricity.",
              "More turns, more electricity, and a soft-iron core make it stronger (like during monsoon rain, the rivers swell and become stronger)."
            ],
    mustRemember: ["Temporary magnet", "Turns + current + soft-iron core"],
  },
  revisionSave: {
    flashcards: [
      { front: "What is an electromagnet?", back: "A solenoid with a soft-iron core; a magnet while current flows." },
      { front: "Three strength factors?", back: "Number of turns, current, soft-iron core." },
      { front: "Why temporary?", back: "Loses magnetism when the current is switched off." },
    ],
    revisionNotes: ["Electromagnet = coil + soft iron", "Stronger: turns, current, core"],
    weakAreaTags: ["electromagnet", "strength factors"],
  },
  qualityFlags: { needsHumanReview: false },
});

// M5 — Applications of Electromagnets
const M5: TuitionLessonSeed = magneticSeed({
  missionId: "M5",
  missionTitle: "Applications of Electromagnets",
  goal: "List the SCERT applications that use electromagnets.",
  estimatedMinutes: 25,
  contentType: "concept",
  tags: ["applications", "electromagnetic crane", "maglev", "MRI", "electric motor"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "An electromagnet can be switched on and off. Where would that be useful in real life?",
    expectedPoints: ["Lifting heavy iron (cranes)", "Machines and scanners"],
    misconceptionCheck: "Students add uses that are not in the SSLC chapter — keep to the textbook applications.",
  },
  teach: {
    teacherIntro: "Chellam, you know how a simple switch can turn on and off the light in your home? Well, electromagnets work in a similar way, and because they can be made very strong, they are used in many cool devices we will learn about in this chapter.",
    explanationBlocks: [
      {
        heading: "Electromagnetic crane",
        explanation: "A crane with an electromagnet lifts heavy iron and steel when the current is on and drops them when it is off.",
        keyTerms: ["electromagnetic crane"],
      },
      {
        heading: "Transport and medicine",
        explanation: "The chapter's figure shows the Maglev train and the MRI scanner as devices that use strong electromagnets.",
        keyTerms: ["Maglev train", "MRI scanner"],
      },
      {
        heading: "Electric motor",
        explanation: "The electric motor also uses the magnetic effect of current — it is shown among the applications in the chapter.",
        keyTerms: ["electric motor"],
      },
    ],
    analogy: "The on/off magnet is like a hand you can make sticky only when you want to pick something up.",
    malayalamSupport: "വൈദ്യുതകാന്തത്തിന്റെ ഉപയോഗങ്ങൾ: ക്രെയിൻ (ഇരുമ്പ് ഉയർത്താൻ), Maglev ട്രെയിൻ, MRI സ്കാനർ, ഇലക്ട്രിക് മോട്ടോർ.",
    manglishSupport: "Electromagnet uses: crane (iron uyarthaan), Maglev train, MRI scanner, electric motor.",
  },
  visualBoard: {
    boardTitle: "Where electromagnets are used",
    frames: [
      {
        id: "m5-f1",
        title: "Crane lifts iron",
        teacherAction: "Draw a crane with an electromagnet lifting scrap iron; note on/off control.",
        boardText: ["Current ON → lifts iron", "Current OFF → drops it"],
        diagramDescription: "Crane arm with an electromagnet holding iron pieces.",
        imageUrl: "assets/textbook-figures/img_page75_idx5.png",
        studentFocus: "On/off control is the key advantage.",
      },
      {
        id: "m5-f2",
        title: "Other applications",
        teacherAction: "List Maglev train, MRI scanner and electric motor.",
        boardText: ["Maglev train", "MRI scanner", "Electric motor"],
        studentFocus: "Stay with the chapter's own examples.",
      },
    ],
  },
  docDoeTrick: {
    title: "Crane-Maglev-MRI-Motor",
    trick: "Four chapter uses: Crane, Maglev, MRI, Motor.",
    whyItWorks: "Four fixed examples keep your answer inside the syllabus instead of drifting to random uses.",
  },
  keyNotes: [
          "Just like a switch, electromagnets can be turned on and off.",
          "Imagine a powerful crane that can lift heavy loads, it uses electromagnets to do its job.",
          "You know how Maglev trains can move without wheels? It's because they use strong electromagnets to float above the track.",
          "Doctors use a special machine called MRI to see inside our bodies, and it uses a strong electromagnet to do that.",
          "The electric motor in your toy car or fan uses the magnetic effect of electricity to make it move."
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 2,
      question: "Write any two devices that use electromagnets.",
      answerPoints: ["Electromagnetic crane (to lift iron and steel).", "Maglev train / MRI scanner / electric motor."],
      keywords: ["crane", "maglev train", "MRI scanner", "electric motor"],
      commonMistakes: ["Listing uses not in the chapter", "Naming permanent-magnet devices"],
      boardStyleRewrite: "Electromagnets are used in electromagnetic cranes to lift iron, and in devices such as the Maglev train, the MRI scanner and the electric motor.",
    },
  ],
  yourTurn: {
    prompt: "Why is an electromagnet, rather than a permanent magnet, used in a scrap-lifting crane? (2 marks)",
    expectedAnswerPoints: ["It can be switched on to lift and off to drop the load", "Its strength can be made very large"],
    hint: "Think about how the crane releases the iron.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "Can be switched on/off to lift and release", marks: 1, requiredKeywords: ["switch", "off"] },
      { point: "Can be made very strong", marks: 1, requiredKeywords: ["strong"] },
    ],
    commonMissingParts: ["The on/off control", "That it can be made very strong"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m5-q1",
      type: "mcq",
      question: "Which device uses an electromagnet to lift heavy iron?",
      options: ["a compass", "an electromagnetic crane", "a bar magnet", "a battery"],
      answer: "an electromagnetic crane",
      explanation: "Cranes use electromagnets so the load can be picked up and dropped on demand.",
      difficulty: "easy",
      tags: ["electromagnetic crane"],
    },
    {
      id: "m5-q2",
      type: "short",
      question: "Name one medical device from the chapter that uses a strong electromagnet.",
      answer: "The MRI scanner.",
      explanation: "The MRI scanner is shown among the electromagnet applications.",
      difficulty: "medium",
      tags: ["MRI"],
    },
  ],
  recap: {
    summary: [
              "Electromagnets: on/off + very strong, they are used in cranes, Maglev trains, MRI scanners and electric motors. Just remember what we learned in this chapter!"
            ],
    mustRemember: ["Crane lifts iron", "On/off control is the advantage"],
  },
  revisionSave: {
    flashcards: [
      { front: "Why an electromagnet in a crane?", back: "It can be switched on/off and made very strong." },
      { front: "Two chapter applications?", back: "Crane and Maglev/MRI/electric motor." },
    ],
    revisionNotes: ["Uses: crane, Maglev, MRI, motor", "On/off is the key advantage"],
    weakAreaTags: ["applications", "electromagnet"],
  },
  hotspot: {
    title: "Motor Principle",
    type: "hotspot",
    importantNote: "Current-carrying conductor in a magnetic field experiences a force. Fleming's Left Hand Rule!"
  },
  qualityFlags: { needsHumanReview: false },
});

// M6 — Force on a Current-Carrying Conductor
const M6: TuitionLessonSeed = magneticSeed({
  missionId: "M6",
  missionTitle: "Force on a Current-Carrying Conductor",
  goal: "Explain that a current-carrying conductor in a magnetic field experiences a force, and what its direction depends on.",
  estimatedMinutes: 30,
  contentType: "concept",
  tags: ["force on conductor", "magnetic field", "current", "direction of force", "Fleming's left hand rule"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "You have seen a magnet push a compass needle. What might happen to a wire carrying current placed between the poles of a magnet?",
    expectedPoints: ["The wire experiences a force", "It moves"],
    misconceptionCheck: "Students think the force is along the current — it is actually perpendicular to both the current and the field.",
  },
  teach: {
    teacherIntro: "Imagine you have a motor boat in the monsoon rain. The rain is like the electric current, and the wind is like the magnetic field. The boat will move, right? That's because the rain (current) and the wind (field) are working together. That's the magic of the electric motor.",
    explanationBlocks: [
      {
        heading: "The conductor experiences a force",
        explanation: "Place a conductor AB between the poles of a magnet and pass current: the conductor moves, because it experiences a force.",
        keyTerms: ["force on conductor", "moves"],
      },
      {
        heading: "What the direction depends on",
        explanation: "The direction of the force depends on the direction of the current and the direction of the magnetic field; the current, field and force are mutually perpendicular.",
        keyTerms: ["direction of current", "direction of field", "perpendicular"],
      },
      {
        heading: "Fleming's left hand rule",
        explanation: "Hold the left thumb, first finger and second finger mutually perpendicular. First finger shows the magnetic field, second finger shows the current, and thumb shows the force/motion.",
        keyTerms: ["Fleming's left hand rule", "field", "current", "force"],
      },
      {
        heading: "Reversing directions",
        explanation: "Reversing only the current, or only the field, reverses the force. Reversing both together keeps the force in the same direction.",
        keyTerms: ["reverse current", "reverse field"],
      },
    ],
    analogy: "The field and the current 'push sideways' on each other — the wire jumps out of the way, at right angles to both.",
    malayalamSupport: "കാന്തികക്ഷേത്രത്തിൽ വൈദ്യുതി ഒഴുകുന്ന ചാലകത്തിന് ബലം അനുഭവപ്പെടുന്നു. ബലത്തിന്റെ ദിശ വൈദ്യുതിയുടെയും ക്ഷേത്രത്തിന്റെയും ദിശയെ ആശ്രയിക്കുന്നു.",
    manglishSupport: "Magnetic field-il current ozhukunna conductor-inu force undaakum. Force direction current-inteyum field-inteyum direction-ne asrayikkum.",
  },
  visualBoard: {
    boardTitle: "Force on a conductor in a magnetic field",
    frames: [
      {
        id: "m6-f1",
        title: "Conductor moves",
        teacherAction: "Draw conductor AB between N and S poles; show it moving when current flows.",
        boardText: ["Conductor AB between magnet poles", "Current ON → conductor moves"],
        diagramDescription: "Magnet poles N–S with conductor AB between them; arrow shows motion.",
        imageUrl: "assets/textbook-figures/img_page77_idx3.png",
        studentFocus: "Current + field → force → motion.",
      },
      {
        id: "m6-f2",
        title: "Left-hand rule",
        teacherAction: "Draw the left hand with first finger = magnetic field, second finger = current, thumb = force/motion.",
        boardText: ["First finger → field", "Second finger → current", "Thumb → force/motion"],
        studentFocus: "Fleming's left hand rule gives the direction of motion.",
      },
    ],
  },
  docDoeTrick: {
    title: "F-C-M",
    trick: "First finger = field, seCond finger = current, thuMb = motion.",
    whyItWorks: "The capital letters F, C and M match Fleming's left hand rule and stop finger mix-ups.",
  },
  keyNotes: [
          "A current-carrying conductor in a magnetic field experiences a force, like a coconut tree falling in the monsoon rain.",
          "The force direction depends on the current direction and the field direction, like how you hold your hands while walking in the rain.",
          "The current, magnetic field and force are mutually perpendicular, like the three wheels of a bicycle: one for the current, one for the field, and one for the force.",
          "Fleming's left hand rule gives the force/motion direction: first finger = field, second finger = current, thumb = motion, like how you would grip a football.",
          "Reversing only the current, or only the field, reverses the force, like changing the direction of your auto rickshaw in the traffic."
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 2,
      question: "What are the factors that influence the direction of the force on a current-carrying conductor in a magnetic field?",
      answerPoints: ["The direction of the current in the conductor.", "The direction of the magnetic field."],
      keywords: ["direction of current", "direction of magnetic field"],
      commonMistakes: ["Saying the force is along the current", "Mixing up the first finger and second finger in Fleming's left hand rule"],
      boardStyleRewrite: "The direction of the force depends on the direction of the current and the direction of the magnetic field. Fleming's left hand rule is used: first finger shows field, second finger shows current, and thumb shows force/motion.",
    },
  ],
  yourTurn: {
    prompt: "A conductor in a magnetic field moves up when current flows. What happens if only the current is reversed? (2 marks)",
    expectedAnswerPoints: ["The force reverses", "The conductor moves down"],
    hint: "Reversing one of current/field reverses the force.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "States the force/motion reverses", marks: 1, requiredKeywords: ["reverse"] },
      { point: "States it now moves the opposite way (down)", marks: 1, requiredKeywords: ["down", "opposite"] },
    ],
    commonMissingParts: ["That the force reverses", "The new direction of motion"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m6-q1",
      type: "mcq",
      question: "A current-carrying conductor in a magnetic field experiences a force that is",
      options: ["along the current", "along the field", "perpendicular to both current and field", "always zero"],
      answer: "perpendicular to both current and field",
      explanation: "The current, field and force are mutually perpendicular.",
      difficulty: "medium",
      tags: ["direction of force"],
    },
    {
      id: "m6-q2",
      type: "short",
      question: "Name the two factors that decide the direction of the force on the conductor.",
      answer: "The direction of the current and the direction of the magnetic field.",
      explanation: "Both directions together fix the direction of the force.",
      difficulty: "medium",
      tags: ["force on conductor"],
    },
  ],
  recap: {
    summary: [
              "Current + field → force on the conductor, like cooking oil + water makes a smooth paste.",
              "Force is perpendicular to current and field, like the four walls of a square room.",
              "Fleming's left hand rule gives motion direction, like following a recipe to make a delicious dish."
            ],
    mustRemember: ["First finger = field", "Second finger = current", "Thumb = motion/force"],
  },
  revisionSave: {
    flashcards: [
      { front: "What does a current-carrying conductor in a field experience?", back: "A force (it moves)." },
      { front: "Force direction depends on?", back: "The current direction and the field direction." },
      { front: "Fleming's left hand rule: thumb shows?", back: "The direction of force/motion." },
      { front: "Reverse only the current - what happens?", back: "The force reverses." },
    ],
    revisionNotes: ["Force is perpendicular to current and field", "Fleming's left hand rule: field-current-motion"],
    weakAreaTags: ["force on conductor", "direction of force"],
  },
  quizTimer: {
    question: "In Fleming's Left Hand Rule, what does the forefinger point to?",
    options: ["Current", "Motion", "Magnetic Field", "Voltage"],
    answer: "Magnetic Field",
    countdownSeconds: 1.5
  },
  qualityFlags: { needsHumanReview: false },
});

// M7 — Electric Motor and the Split-Ring Commutator
const M7: TuitionLessonSeed = magneticSeed({
  missionId: "M7",
  missionTitle: "Electric Motor and the Split-Ring Commutator",
  goal: "Explain how an electric motor rotates and why it needs a split-ring commutator.",
  estimatedMinutes: 35,
  contentType: "diagram",
  tags: ["electric motor", "split-ring commutator", "coil", "rotation", "energy conversion"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "A conductor in a magnetic field feels a force. What happens if we use a coil (two sides) instead of a single wire?",
    expectedPoints: ["The two sides feel opposite forces", "The coil rotates"],
    misconceptionCheck: "Students forget why the coil keeps turning the same way — the commutator does that job.",
  },
  teach: {
    teacherIntro: "Imagine a strong fan. We put it in a coconut tree. It will turn with the wind. This fan gets energy from the electricity. It turns into a strong wind (rotational energy)!",
    explanationBlocks: [
      {
        heading: "Opposite forces rotate the coil",
        explanation: "In a rectangular coil between magnet poles, sides AB and CD carry current in opposite directions, so they feel forces in opposite directions. This turning effect rotates the coil.",
        keyTerms: ["coil", "opposite forces", "rotation"],
      },
      {
        heading: "The split-ring commutator",
        explanation: "The split-ring commutator reverses the direction of current in the coil every half rotation, so the coil keeps rotating in the same direction.",
        keyTerms: ["split-ring commutator", "reverses current"],
      },
      {
        heading: "Energy conversion",
        explanation: "The motor converts electrical energy into mechanical (rotational) energy.",
        keyTerms: ["electrical energy", "mechanical energy"],
      },
    ],
    analogy: "The commutator is like a hand that flips the coil's current at the right moment so the push always turns it the same way.",
    malayalamSupport: "ഇലക്ട്രിക് മോട്ടോർ: കോയിലിന്റെ AB, CD വശങ്ങളിൽ വിപരീത ബലം → കറക്കം. സ്പ്ലിറ്റ്-റിംഗ് കമ്മ്യൂട്ടേറ്റർ ഓരോ അർധ കറക്കത്തിലും വൈദ്യുതി ദിശ മാറ്റുന്നു. വൈദ്യുതോർജ്ജം → യാന്ത്രികോർജ്ജം.",
    manglishSupport: "Electric motor: coil-inte AB, CD-yil opposite force → rotation. Split-ring commutator oro half rotation-ilum current direction maattum. Electrical → mechanical energy.",
  },
  visualBoard: {
    boardTitle: "How an electric motor works",
    frames: [
      {
        id: "m7-f1",
        title: "Coil between magnet poles",
        teacherAction: "Draw a rectangular coil AB–CD between N and S poles; mark opposite forces on AB and CD.",
        boardText: ["AB and CD carry current in opposite directions", "Opposite forces → the coil turns"],
        diagramDescription: "Rectangular coil between magnet poles with force arrows up on one side, down on the other.",
        imageUrl: "assets/textbook-figures/img_page77_idx5.png",
        studentFocus: "Opposite forces on the two sides cause rotation.",
      },
      {
        id: "m7-f2",
        title: "Split-ring commutator",
        teacherAction: "Draw the split rings and brushes; explain the current reverses each half turn.",
        boardText: ["Split-ring commutator + brushes", "Reverses current every half turn → same-direction spin"],
        diagramDescription: "Coil ends connected to a split ring with two brushes and a battery.",
        imageUrl: "assets/textbook-figures/img_page82_idx2.png",
        studentFocus: "Commutator keeps the rotation in one direction.",
      },
    ],
  },
  docDoeTrick: {
    title: "Opposite forces + commutator",
    trick: "Opposite forces on AB and CD spin the coil; the split-ring commutator flips the current each half turn to keep it spinning one way.",
    whyItWorks: "It links the two mark-earning ideas — the turning effect and the commutator's job.",
  },
  keyNotes: [
          "An electric motor changes electrical energy into rotational energy.",
          "The coil has two sides, AB and CD. They carry electricity in opposite directions like water flowing in two opposite directions in a river.",
          "Because of this opposite electricity, they get opposite forces. Like when two friends pull a rope in opposite directions, the rope will turn around.",
          "A special part called the commutator helps the coil turn in one direction. It's like a traffic signal that says, 'Go left, go left!' and 'Now go right, now go right!'",
          "The commutator changes the electricity direction every half rotation. This way, the coil keeps turning in the same direction, like a bike moving forward."
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 4,
      question: "How does an electric motor work?",
      answerPoints: [
        "A current-carrying coil is placed between the poles of a magnet.",
        "Its two sides carry current in opposite directions and feel opposite forces, so the coil rotates.",
        "The split-ring commutator reverses the current every half rotation.",
        "This keeps the coil rotating in the same direction; electrical energy becomes mechanical energy.",
      ],
      keywords: ["coil", "magnetic field", "opposite forces", "rotation", "split-ring commutator"],
      commonMistakes: ["Omitting the commutator's role", "Not saying the forces are opposite on the two sides"],
      boardStyleRewrite: "A current-carrying coil between magnet poles has opposite forces on its two sides, which rotate it. The split-ring commutator reverses the current every half turn, keeping the rotation in one direction, converting electrical energy to mechanical energy.",
    },
    {
      marks: 2,
      question: "What is the necessity of a split-ring commutator in an electric motor?",
      answerPoints: ["It reverses the direction of current in the coil every half rotation.", "This keeps the coil rotating continuously in the same direction."],
      keywords: ["reverses current", "half rotation", "same direction", "continuous"],
      commonMistakes: ["Saying it supplies current only", "Not mentioning the same-direction rotation"],
      boardStyleRewrite: "The split-ring commutator reverses the current in the coil every half rotation, so the coil keeps rotating continuously in the same direction.",
    },
  ],
  yourTurn: {
    prompt: "Why do the two sides of the motor coil experience forces in opposite directions? (2 marks)",
    expectedAnswerPoints: ["The two sides carry current in opposite directions", "So the force on each side is opposite, producing rotation"],
    hint: "Compare the current direction in AB and CD.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "Two sides carry current in opposite directions", marks: 1, requiredKeywords: ["opposite", "current"] },
      { point: "So the forces are opposite → rotation", marks: 1, requiredKeywords: ["force", "rotat"] },
    ],
    commonMissingParts: ["Opposite current directions", "That this gives rotation"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m7-q1",
      type: "mcq",
      question: "The part of an electric motor that reverses the current every half rotation is the",
      options: ["armature", "split-ring commutator", "field magnet", "brush only"],
      answer: "split-ring commutator",
      explanation: "The split-ring commutator reverses the current each half turn to keep rotation in one direction.",
      difficulty: "easy",
      tags: ["split-ring commutator"],
    },
    {
      id: "m7-q2",
      type: "short",
      question: "What energy conversion takes place in an electric motor?",
      answer: "Electrical energy into mechanical (rotational) energy.",
      explanation: "The motor uses the magnetic force on a coil to produce rotation.",
      difficulty: "medium",
      tags: ["energy conversion"],
    },
  ],
  recap: {
    summary: [
              "The coil turns because of opposite forces. The commutator helps it turn in one direction. Electrical energy becomes rotational energy!"
            ],
    mustRemember: ["Commutator = continuous same-direction spin", "Motor: electrical → mechanical"],
  },
  revisionSave: {
    flashcards: [
      { front: "What rotates the motor coil?", back: "Opposite forces on its two sides." },
      { front: "Job of the split-ring commutator?", back: "Reverses current every half turn to keep spinning one way." },
      { front: "Motor energy conversion?", back: "Electrical → mechanical (rotational)." },
    ],
    revisionNotes: ["Motor: opposite forces + commutator", "Electrical → mechanical energy"],
    weakAreaTags: ["electric motor", "split-ring commutator"],
  },
  qualityFlags: { needsHumanReview: false },
});

// M8 — Moving-Coil Loudspeaker
const M8: TuitionLessonSeed = magneticSeed({
  missionId: "M8",
  missionTitle: "Moving-Coil Loudspeaker",
  goal: "Explain how a moving-coil loudspeaker uses the magnetic effect of current to produce sound.",
  estimatedMinutes: 25,
  contentType: "concept",
  tags: ["loudspeaker", "voice coil", "diaphragm", "sound", "energy conversion"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "A motor turns electrical energy into motion. How could a similar idea produce sound in a speaker?",
    expectedPoints: ["A coil in a magnetic field vibrates", "The vibration makes sound"],
    misconceptionCheck: "Students think the speaker 'stores' sound — it converts electrical signals into vibrations.",
  },
  teach: {
    teacherIntro: "A loudspeaker is like a coconut tree in the wind. When the wind blows, the coconut tree shakes. Similarly, a moving-coil loudspeaker works on the motor principle. When an audio signal comes, the coil carrying the signal shakes in a strong magnetic field, making sound.",
    explanationBlocks: [
      {
        heading: "The parts",
        explanation: "It has a voice coil around a field magnet, and the coil is attached to a paper diaphragm.",
        keyTerms: ["voice coil", "field magnet", "diaphragm"],
      },
      {
        heading: "How it makes sound",
        explanation: "Audio signals (changing current) in the voice coil, sitting in the magnetic field, make the coil vibrate; the attached diaphragm vibrates and produces sound.",
        keyTerms: ["audio signal", "vibrates", "sound"],
      },
      {
        heading: "Energy conversion",
        explanation: "The loudspeaker converts electrical energy into sound energy.",
        keyTerms: ["electrical energy", "sound energy"],
      },
    ],
    analogy: "The voice coil is a tiny motor that shakes the paper cone; the shaking paper pushes air and you hear sound.",
    malayalamSupport: "മൂവിംഗ്-കോയിൽ ലൗഡ്‌സ്പീക്കർ: വോയ്‌സ് കോയിലിലെ ഓഡിയോ സിഗ്നൽ കാന്തികക്ഷേത്രത്തിൽ കമ്പനം ഉണ്ടാക്കുന്നു; ഡയഫ്രം കമ്പിച്ച് ശബ്ദം. വൈദ്യുതോർജ്ജം → ശബ്ദോർജ്ജം.",
    manglishSupport: "Moving-coil loudspeaker: voice coil-ile audio signal magnetic field-il vibration undaakum; diaphragm vibrate cheythu sound. Electrical → sound energy.",
  },
  visualBoard: {
    boardTitle: "Moving-coil loudspeaker",
    frames: [
      {
        id: "m8-f1",
        title: "Parts of the speaker",
        teacherAction: "Draw the field magnet, voice coil around it, and the paper diaphragm attached to the coil.",
        boardText: ["Voice coil + field magnet", "Diaphragm attached to the coil"],
        diagramDescription: "Field magnet with a voice coil and a paper diaphragm connected to it.",
        imageUrl: "assets/textbook-figures/img_page84_idx4.png",
        studentFocus: "Coil in a field, attached to a diaphragm.",
      },
      {
        id: "m8-f2",
        title: "Signal → sound",
        teacherAction: "Show audio signal → coil vibrates → diaphragm vibrates → sound.",
        boardText: ["Audio signal → coil vibrates", "Diaphragm vibrates → sound", "Electrical → sound energy"],
        studentFocus: "Electrical signal becomes sound.",
      },
    ],
  },
  docDoeTrick: {
    title: "Coil shakes, diaphragm sounds",
    trick: "Audio signal shakes the voice coil in the magnet; the diaphragm shakes and makes sound.",
    whyItWorks: "It traces the one-line energy path: electrical signal → vibration → sound.",
  },
  keyNotes: [
          "A moving-coil loudspeaker uses the motor principle.",
          "It has a special coil and magnet inside. The coil is like the driver of an auto rickshaw, moving in the strong magnetic field like the rickshaw moving on the road.",
          "Audio signals in the coil make it vibrate like a football player dancing in celebration.",
          "The diaphragm vibrates and produces sound like the drums in a band.",
          "It converts electrical energy into sound energy like a chef cooking food in a kitchen."
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 1,
      question: "What is the energy conversion in a moving-coil loudspeaker?",
      answerPoints: ["Electrical energy is converted into sound energy."],
      keywords: ["electrical energy", "sound energy"],
      commonMistakes: ["Saying mechanical to sound only", "Naming the wrong energy"],
      boardStyleRewrite: "A moving-coil loudspeaker converts electrical energy into sound energy.",
    },
  ],
  yourTurn: {
    prompt: "What is the function of the diaphragm in a moving-coil loudspeaker? (2 marks)",
    expectedAnswerPoints: ["It is attached to the vibrating voice coil", "Its vibration produces the sound"],
    hint: "Link the coil's vibration to the sound.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "The diaphragm is attached to the voice coil", marks: 1, requiredKeywords: ["coil", "attached"] },
      { point: "Its vibration produces sound", marks: 1, requiredKeywords: ["vibrat", "sound"] },
    ],
    commonMissingParts: ["Link to the voice coil", "That vibration makes sound"],
    feedbackTemplate: "You wrote {covered}. Add {missing} for full marks.",
  },
  quiz: [
    {
      id: "m8-q1",
      type: "mcq",
      question: "A moving-coil loudspeaker converts electrical energy mainly into",
      options: ["light energy", "sound energy", "heat energy", "chemical energy"],
      answer: "sound energy",
      explanation: "The vibrating diaphragm converts the electrical signal into sound.",
      difficulty: "easy",
      tags: ["energy conversion"],
    },
    {
      id: "m8-q2",
      type: "short",
      question: "Which part of the loudspeaker carries the audio signal in the magnetic field?",
      answer: "The voice coil.",
      explanation: "The voice coil sits in the field magnet and vibrates with the audio signal.",
      difficulty: "medium",
      tags: ["voice coil"],
    },
  ],
  recap: {
    summary: [
              "Loudspeaker uses the motor principle like a coconut tree in the wind.",
              "Voice coil vibrates in the strong magnetic field like an auto rickshaw driver.",
              "Diaphragm vibrates → sound like a football player dancing or a chef cooking food."
            ],
    mustRemember: ["Electrical → sound energy", "Voice coil + diaphragm"],
  },
  revisionSave: {
    flashcards: [
      { front: "Loudspeaker energy conversion?", back: "Electrical → sound energy." },
      { front: "Part that vibrates to make sound?", back: "The diaphragm (driven by the voice coil)." },
    ],
    revisionNotes: ["Loudspeaker = motor-principle device", "Electrical → sound via vibrating diaphragm"],
    weakAreaTags: ["loudspeaker", "energy conversion"],
  },
  qualityFlags: { needsHumanReview: false },
});

// M9 — Exam Answer Practice
const M9: TuitionLessonSeed = magneticSeed({
  missionId: "M9",
  missionTitle: "Exam Answer Practice — Magnetic Effect of Electric Current",
  goal: "Write board-style answers for the key questions of the chapter with the right keywords.",
  estimatedMinutes: 30,
  contentType: "exam_answer",
  tags: ["exam answer", "keywords", "board style", "structure"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "Name three exam keywords from this chapter you must not miss.",
    expectedPoints: ["right-hand thumb rule", "split-ring commutator", "soft-iron core"],
    misconceptionCheck: "Students give the right idea but drop the exact keyword the rubric rewards.",
  },
  teach: {
    teacherIntro: "You will get good marks if you use the right words and answer in a clear order. First, say the answer clearly. Then, write the important words from the chapter. Finally, finish with a short sentence.",
    explanationBlocks: [
      {
        heading: "Rule answers",
        explanation: "For the right-hand thumb rule: right hand, thumb = current, curled fingers = field. State the hand and both meanings.",
        keyTerms: ["right-hand thumb rule"],
      },
      {
        heading: "Electromagnet answers",
        explanation: "For strength: number of turns, current, soft-iron core — three keywords, three marks.",
        keyTerms: ["number of turns", "current", "soft-iron core"],
      },
      {
        heading: "Motor / commutator answers",
        explanation: "For the motor: opposite forces rotate the coil; the split-ring commutator reverses current each half turn to keep it spinning one way.",
        keyTerms: ["opposite forces", "split-ring commutator"],
      },
    ],
    malayalamSupport: "ഉത്തരത്തിൽ കീവേഡുകൾ (right-hand thumb rule, soft-iron core, split-ring commutator) നിർബന്ധമായും ഉൾപ്പെടുത്തുക. ഘടന: പോയിന്റ് → കീവേഡ് → ക്ലോസ്.",
    manglishSupport: "Answer-il keywords (right-hand thumb rule, soft-iron core, split-ring commutator) nirbandhamaayi cheythu vekkuka. Structure: point → keyword → close.",
  },
  visualBoard: {
    boardTitle: "Answer skeletons with keywords",
    frames: [
      {
        id: "m9-f1",
        title: "2-mark skeleton",
        teacherAction: "Write a 2-line skeleton with blanks for keywords.",
        boardText: ["Line 1: direct answer (+ keyword)", "Line 2: one support line"],
        studentFocus: "Definition/point + keyword = 2 marks.",
      },
      {
        id: "m9-f2",
        title: "4-mark skeleton (motor)",
        teacherAction: "Write: coil → opposite forces → commutator → energy conversion.",
        boardText: ["Coil in field", "Opposite forces → rotation", "Commutator reverses current", "Electrical → mechanical"],
        studentFocus: "Four keyword points = 4 marks.",
      },
    ],
  },
  docDoeTrick: {
    title: "Point-Keyword-Close",
    trick: "Every answer: Point → Keywords → Close.",
    whyItWorks: "It guarantees the structure and keyword coverage the rubric rewards.",
  },
  keyNotes: [
          "Start with a clear answer sentence.",
          "Use the exact words from the chapter.",
          "Remember this trick: your right hand = current, fingers = field.",
          "A strong electromagnet needs many turns, a lot of current, and a soft-iron core.",
          "A motor works when opposite forces pull, there's a split-ring commutator, and electricity turns into movement."
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 3,
      question: "State three factors affecting the strength of an electromagnet (board style).",
      answerPoints: ["Number of turns of the coil.", "Current through the coil.", "Use of a soft-iron core."],
      keywords: ["number of turns", "current", "soft-iron core"],
      commonMistakes: ["Listing only current", "Forgetting the soft-iron core"],
      boardStyleRewrite: "The strength of an electromagnet increases with the number of turns, the current, and by using a soft-iron core.",
    },
    {
      marks: 4,
      question: "Explain the working of an electric motor (board style).",
      answerPoints: [
        "A current-carrying coil is placed between the poles of a magnet.",
        "Its two sides feel opposite forces and the coil rotates.",
        "The split-ring commutator reverses the current every half rotation.",
        "The coil keeps rotating one way; electrical energy becomes mechanical energy.",
      ],
      keywords: ["coil", "opposite forces", "split-ring commutator", "mechanical energy"],
      commonMistakes: ["Omitting the commutator", "Not naming the energy conversion"],
      boardStyleRewrite: "A current-carrying coil between magnet poles feels opposite forces on its two sides and rotates. The split-ring commutator reverses the current each half turn, keeping it rotating one way and converting electrical energy to mechanical energy.",
    },
  ],
  yourTurn: {
    prompt: "Write a 2-mark answer: 'Why is a split-ring commutator used in an electric motor?'",
    expectedAnswerPoints: ["It reverses the current every half rotation", "So the coil keeps rotating in the same direction"],
    hint: "Point → keywords (reverses current, same direction) → close.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "Reverses the current every half rotation", marks: 1, requiredKeywords: ["reverse", "current"] },
      { point: "Keeps the coil rotating in the same direction", marks: 1, requiredKeywords: ["same direction", "rotat"] },
    ],
    commonMissingParts: ["That it reverses the current", "The same-direction rotation"],
    feedbackTemplate: "You wrote {covered}. Add {missing} to score full.",
  },
  quiz: [
    {
      id: "m9-q1",
      type: "short",
      question: "Which keyword must appear in a right-hand thumb rule answer besides 'current'?",
      answer: "Curled fingers (field direction) / right hand.",
      explanation: "Examiners look for the right hand and the curled-fingers-give-field idea.",
      difficulty: "exam",
      tags: ["right-hand thumb rule", "keyword"],
    },
    {
      id: "m9-q2",
      type: "short",
      question: "In a motor answer, name two keywords you must include.",
      answer: "Any two of: opposite forces, split-ring commutator, rotation, mechanical energy.",
      explanation: "These are the rubric keywords for the motor.",
      difficulty: "medium",
      tags: ["keywords"],
    },
  ],
  recap: {
    summary: [
              "Answer → Keywords → Finish",
              "Use the exact chapter words.",
              "Write one sentence for each point, and you will get 4 marks."
            ],
    mustRemember: ["Keywords win marks", "Structure matters as much as content"],
  },
  revisionSave: {
    flashcards: [
      { front: "Right-hand rule answer keywords?", back: "Right hand, thumb = current, curled fingers = field." },
      { front: "Electromagnet strength keywords?", back: "Number of turns, current, soft-iron core." },
      { front: "Motor answer keywords?", back: "Opposite forces + split-ring commutator + electrical→mechanical." },
    ],
    revisionNotes: ["Answer = Point + Keywords + Close", "Lock the chapter keywords"],
    weakAreaTags: ["exam answer writing", "board keywords"],
  },
  qualityFlags: { needsHumanReview: false },
});

// M10 — Revision Mission
const M10: TuitionLessonSeed = magneticSeed({
  missionId: "M10",
  missionTitle: "Revision Mission — Magnetic Effect of Electric Current",
  goal: "Revise the definitions, rules, diagrams, applications and traps of the chapter.",
  estimatedMinutes: 25,
  contentType: "revision",
  tags: ["revision", "rules", "flashcards", "traps", "applications"],
  sourceRefs: [MAGNETIC_SOURCE],
  sourceStatus: "source_backed",
  canTeach: true,
  pyqEvidenceStatus: "not_curated",
  recall: {
    prompt: "From memory: which hand rule gives the field around a wire, and what does a split-ring commutator do?",
    expectedPoints: ["Right-hand thumb rule", "Commutator reverses current each half turn"],
    misconceptionCheck: "Quick check that right-hand vs left-hand and the commutator's job are not swapped.",
  },
  teach: {
    teacherIntro: "Chalo, let's revise quickly! Lock the big ideas, the main rules and the tricky parts you must avoid before the test.",
    explanationBlocks: [
      {
        heading: "Ideas to lock",
        explanation: "Current makes a magnetic field (Oersted); solenoid acts like a bar magnet; electromagnet = coil + soft-iron core; conductor in a field feels a force; motor and loudspeaker use this.",
        keyTerms: ["magnetic effect", "solenoid", "electromagnet", "motor"],
      },
      {
        heading: "Rules to lock",
        explanation: "Right-hand thumb rule (field around a wire); solenoid polarity (anticlockwise end = north); force depends on current and field directions (rule name from your text).",
        keyTerms: ["right-hand thumb rule", "solenoid polarity"],
      },
      {
        heading: "Traps to avoid",
        explanation: "Using the left hand; forgetting the soft-iron core; leaving out the split-ring commutator; over-naming the force rule.",
        keyTerms: ["left-hand trap", "commutator trap"],
      },
    ],
    malayalamSupport: "Right-hand thumb rule (wire-inു ചുറ്റും field), solenoid: anticlockwise = north, electromagnet = coil + soft iron. Left hand, soft-iron core, commutator മറക്കരുത്.",
    manglishSupport: "Right-hand thumb rule (wire chuttum field), solenoid anticlockwise = north, electromagnet = coil + soft iron. Left hand / soft-iron core / commutator marakkaruthu.",
  },
  visualBoard: {
    boardTitle: "One-board revision",
    frames: [
      {
        id: "m10-f1",
        title: "Ideas + rules + traps",
        teacherAction: "Write ideas on one side, rules in the middle, traps on the other.",
        boardText: ["Oersted, solenoid, electromagnet, motor, loudspeaker", "Rules: right-hand thumb, solenoid polarity", "Traps: left hand, soft-iron core, commutator"],
        studentFocus: "One glance recalls the whole chapter.",
      },
    ],
  },
  docDoeTrick: {
    title: "3-Lock",
    trick: "Lock Ideas, Lock Rules, Lock Traps.",
    whyItWorks: "Revision only needs these three buckets — fast and complete.",
  },
  keyNotes: [
          "Electric current creates a magnetic field (same as the spark when we touch a wire with a coconut tree in a thunderstorm); field lines are like circles around a straight wire.",
          "Right-hand thumb rule: your thumb is the current, and your curled fingers show you the direction of the magnetic field.",
          "A coil of wire with a soft-iron core acts like a big magnet; this is how an electromagnet works.",
          "When a conductor (like a wire) moves through a magnetic field, it feels a force; this is how an electric motor runs, like a football player running with the ball.",
          "A split-ring commutator helps to reverse the current direction each half turn; this is how a loudspeaker converts electrical energy into sound, like when we cook and the sizzling of vegetables sounds loud, na?"
        ],
  formulas: [],
  examAnswers: [
    {
      marks: 1,
      question: "Which hand rule gives the direction of the magnetic field around a straight current-carrying conductor?",
      answerPoints: ["The right-hand thumb rule."],
      keywords: ["right-hand thumb rule"],
      commonMistakes: ["Saying left-hand rule"],
      boardStyleRewrite: "The right-hand thumb rule gives the direction of the field around a straight conductor.",
    },
  ],
  yourTurn: {
    prompt: "List three common traps in this chapter. (2 marks)",
    expectedAnswerPoints: ["Using the left hand for the thumb rule", "Forgetting the soft-iron core", "Leaving out the split-ring commutator"],
    hint: "Think hand, core, commutator.",
  },
  correctionRubric: {
    maxMarks: 2,
    scoringPoints: [
      { point: "Names the left-hand / core trap", marks: 1, requiredKeywords: ["left", "core"] },
      { point: "Names the commutator trap", marks: 1, requiredKeywords: ["commutator"] },
    ],
    commonMissingParts: ["The hand/core trap", "The commutator trap"],
    feedbackTemplate: "You listed {covered}. Also include {missing}.",
  },
  quiz: [
    {
      id: "m10-q1",
      type: "mcq",
      question: "Which pair is correctly matched?",
      options: ["Field around a wire – left-hand rule", "Solenoid – behaves like a bar magnet", "Electromagnet – permanent magnet", "Motor – no commutator needed"],
      answer: "Solenoid – behaves like a bar magnet",
      explanation: "A solenoid behaves like a bar magnet; the field around a wire uses the right-hand rule.",
      difficulty: "easy",
      tags: ["revision"],
    },
    {
      id: "m10-q2",
      type: "short",
      question: "An electromagnet and a moving-coil loudspeaker both rely on which effect?",
      answer: "The magnetic effect of electric current.",
      explanation: "Both use the magnetic field produced by a current.",
      difficulty: "medium",
      tags: ["magnetic effect"],
    },
  ],
  recap: {
    summary: [
              "Lock in the ideas, rules and traps you must avoid",
              "Right-hand thumb rule; solenoid is like a big magnet",
              "Motor: opposite forces + commutator are like the rhythm of monsoon rain"
            ],
    mustRemember: ["Right hand, not left", "Soft-iron core + commutator earn marks"],
  },
  revisionSave: {
    flashcards: [
      { front: "Field around a straight wire — which rule?", back: "Right-hand thumb rule." },
      { front: "Solenoid behaves like…?", back: "A bar magnet." },
      { front: "Commutator job?", back: "Reverses current each half turn for one-way rotation." },
    ],
    revisionNotes: ["Ideas: Oersted, solenoid, electromagnet, motor, loudspeaker", "Traps: left hand, core, commutator"],
    weakAreaTags: ["revision", "magnetic effect"],
  },
  qualityFlags: { needsHumanReview: false },
});

export const MAGNETIC_EFFECT_SEEDS: TuitionLessonSeed[] = [M1, M2, M3, M4, M5, M6, M7, M8, M9, M10];