| [ |
| { |
| "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": 2 |
| }, |
| { |
| "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": 2 |
| }, |
| { |
| "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": 2 |
| }, |
| { |
| "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": 1 |
| }, |
| { |
| "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 |
| } |
| ] |
