Create answer_key.json

answer_key.json

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+[
+  {
+    "section": "A",
+    "question_number": "1(i)",
+    "answer": "b",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(ii)",
+    "answer": "a",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(iii)",
+    "answer": "c",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(iv)",
+    "answer": "a",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(v)",
+    "answer": "b",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(vi)",
+    "answer": "c",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(vii)",
+    "answer": "d",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(viii)",
+    "answer": "b",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(ix)",
+    "answer": "a",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(x)",
+    "answer": "a",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(xi)",
+    "answer": "b",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(xii)",
+    "answer": "a",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(xiii)",
+    "answer": "c",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(xiv)",
+    "answer": "d",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "1(xv)",
+    "answer": "a",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(i)(a)",
+    "answer": "C¹⁴ is a radioisotope because of the instability of the nucleus. Used for carbon dating.",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(i)(b)",
+    "answer": "Class II lever.",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(ii)(a)",
+    "answer": "Centripetal",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(ii)(b)",
+    "answer": "zero",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(iii)",
+    "answer": "30 N",
+    "marks": 2
+  },
+  {
+    "section": "A",
+    "question_number": "2(iv)(a)",
+    "answer": "Mechanical advantage using a block and tackle system of 9 pulleys is 9 whereas the mechanical advantage of a single moveable pulley is 2.",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(iv)(b)",
+    "answer": "Increase of number of pulley increases mechanical advantage.",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(v)",
+    "answer": "4:1",
+    "marks": 2
+  },
+  {
+    "section": "A",
+    "question_number": "2(vi)(a)",
+    "answer": "Resistance decreases",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(vi)(b)",
+    "answer": "Current (Intensity of light) increases as resistance decreases",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "2(vii)",
+    "answer": "17:10",
+    "marks": 2
+  },
+  {
+    "section": "A",
+    "question_number": "3(i)(a)",
+    "answer": "In between optical centre and focus",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "3(i)(b)",
+    "answer": "Because concave lens produces reduced size image.",
+    "marks": 1
+  },
+  {
+    "section": "A",
+    "question_number": "3(ii)",
+    "answer": "No. The geyser draws I = P/V = 1540/220 = 7A. Hence, 5A rated fuse will blow off for the geyser.",
+    "marks": 2
+  },
+  {
+    "section": "A",
+    "question_number": "3(iii)",
+    "answer": "1. Increasing the number of turns of the armature\n2. Increasing the applied battery e.m.f.",
+    "marks": 2
+  },
+  {
+    "section": "A",
+    "question_number": "3(iv)",
+    "answer": "165,000 J",
+    "marks": 2
+  },
+  {
+    "section": "A",
+    "question_number": "3(v)",
+    "answer": "₉₂U²³⁵ + ₀n¹ → ₅₆Ba¹⁴¹ + ₃₆Kr⁹² + 3₀n¹",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "4(i)",
+    "answer": "f = 24 cm\nPower = 4.17 D",
+    "marks": 3
+  },
+  {
+    "section": "B",
+    "question_number": "4(ii)(a)",
+    "answer": "Microwave",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "4(ii)(b)",
+    "answer": "X-rays",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "4(ii)(c)",
+    "answer": "Both have same speed in vacuum",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "4(iii)(a)",
+    "answer": "Red colour is used as danger signal because it is scattered least due to its longest wavelength in visible range. Hence, it is visible from a very long distance.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "4(iii)(b)1",
+    "answer": "Critical angle is 43°",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "4(iii)(b)2",
+    "answer": "Angle of prism = 43°",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "4(iii)(b)3",
+    "answer": "If the blue ray is replaced by indigo or violet, there will be total internal reflection.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "5(i)(a)",
+    "answer": "8/9",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "5(i)(b)",
+    "answer": "The principle of reversibility",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "5(i)(c)",
+    "answer": "No",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "5(ii)(a)",
+    "answer": "False",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "5(ii)(b)",
+    "answer": "Refractive index = 10t₂/t₁",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "5(iii)(a)",
+    "answer": "[Diagram showing completed ray path]",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "5(iii)(b)",
+    "answer": "1. Angle of incidence\n2. Refractive index",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "6(i)(a)",
+    "answer": "Centre of gravity is the point where the mass of the whole body appears to be concentrated.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(i)(b)1",
+    "answer": "2 cm from base (h/3 = 6/3)",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(i)(b)2",
+    "answer": "Yes",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(ii)(a)",
+    "answer": "Marble A",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(ii)(b)",
+    "answer": "Along both the paths",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(ii)(c)",
+    "answer": "Along both the paths",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(iii)(a)",
+    "answer": "[Diagram showing tackle system with VR=2]",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(iii)(b)1",
+    "answer": "M.A. = 1.6",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "6(iii)(b)2",
+    "answer": "Effort = 30 kgf",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "7(i)(a)",
+    "answer": "Ultrasonic wave",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "7(i)(b)",
+    "answer": "1 s",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "7(ii)(a)",
+    "answer": "²³⁴₉₀Y → ²³⁴₉₁Z + ⁰₋₁e",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "7(ii)(b)",
+    "answer": "U-235",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "7(iii)(a)",
+    "answer": "Resonance",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "7(iii)(b)",
+    "answer": "Natural frequency of the air column matched with the frequency of the tuning fork.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "7(iii)(c)",
+    "answer": "Length of air column should be decrease. Since frequency is inversely proportional to the air column.",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "8(i)(a)",
+    "answer": "Non-ohmic",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "8(i)(b)",
+    "answer": "The resistance is not constant. It increases as voltage and current increases.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "8(i)(c)",
+    "answer": "The flow of current through the conductor is directly proportional to the potential difference established across the conductor provide its physical conditions are constant.",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "8(ii)(a)",
+    "answer": "Step down transformer",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "8(ii)(b)",
+    "answer": "Wire of secondary coil is thicker because secondary current is higher than primary current.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "8(iii)(a)",
+    "answer": "8Ω",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "8(iii)(b)",
+    "answer": "0.5A",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "8(iii)(c)",
+    "answer": "Current in both the resistors are equal because both the arms have same resistance value.",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "9(i)",
+    "answer": "25g",
+    "marks": 3
+  },
+  {
+    "section": "B",
+    "question_number": "9(ii)(a)",
+    "answer": "When lake freezes, it released latent heat to the atmosphere which warms the atmosphere.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "9(ii)(b)",
+    "answer": "Since there is no change of temperature there is no change in kinetic energy.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "9(ii)(c)",
+    "answer": "1 g of ice at 0°C has more heat energy than 1 g water at 0°C.",
+    "marks": 2
+  },
+  {
+    "section": "B",
+    "question_number": "9(iii)(a)",
+    "answer": "Number of turns in armature may be increased.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "9(iii)(b)1",
+    "answer": "Maxwell right hand thumb rule.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "9(iii)(b)2",
+    "answer": "Direction of current is from X to Y.",
+    "marks": 1
+  },
+  {
+    "section": "B",
+    "question_number": "9(iii)(b)3",
+    "answer": "As R increases, current decreases. So, strength of magnetic field decreases.",
+    "marks": 1
+  }
+]