Class 12th JEE MRJM/12 Milestone Test-0 Phase-2 DATE: 09/06/2024 M.MARKS: 300 DURATION: 180 Minutes Topic Covered Physics : Electric Charges and Fields Chemistry : Solutions, Electrochemistry Mathematics : Determinants, Matrices GENERAL INSTRUCTION 1. 2. 3. 4. 5. 6. 7. 8. Immediately fill in the particulars on this page of the test booklet. The test is of 3 hours duration. The test booklet consists of 90 questions. The maximum marks are 300. There are three sections in this question paper. Sections I, II and III, are of Physics, Chemistry and Mathematics, respectively. Each section consists of 30 questions, of which the first 20 are mandatory and are of Multiple Option type and the last 10 are of integer answer type. You need to attempt any 5 integer type questions (out of 10) in each of the three sections. There is only one correct response for each question. Each correct answer will give 4 marks while 1 Mark will be deducted for a wrong response. No student is allowed to carry any textual material, printed or written, bits of papers, pager, mobile phone, any electronic device, etc. inside the examination room/hall. On completion of the test, the candidate must hand over the Answer Sheet to the Invigilator on duty in the Room/Hall. However, the candidates are allowed to take away this Test Booklet with them. SECTION-I (PHYSICS) Single Correct Type Questions (1-20) 1. A thin conducting ring of radius R is given a charge +Q. The electric field at the centre O of the 5. A comb run through one’s dry hair attracts small bits of paper. This is due to (1) Comb is good conductor (2) Paper is good conductor (3) The atoms in the paper get polarized by the charged comb (4) The comb possesses magnetic properties 6. The electric field due to an electric dipole at a distance r from its centre in axial position is E . If the dipole is rotated through an angle of 90° about its perpendicular axis, the electric field at the same point will be (Note: r is very larger than dipole length) E (1) E (2) 4 E (4) 2E (3) 2 7. Three infinitely large non conducting charged sheets are placed as shown in figure. The electric field at point P is ring due to the charge on the part AKB of the ring is E. The electric field at the centre due to the charge on the part ACDB of the ring is 2. 3. (1) E along KO (2) 3 along E OK (3) 3 along E KO (4) E along OK Two charges of equal magnitudes and at a distance r exert a force F on each other. If the charges are halved and distance between them is doubled, then the new force acting on each charge is (1) F /8 (2) F /4 (4) F /16 (3) 4 F z A pendulum bob of mass 30.7 × 10−6 kg and carrying a charge 2 × 10−8 C is at rest in a N horizontal uniform electric field of 20000 . The C tension in the thread of the pendulum will be ( approximately g = 9.8 m/s 2 4. ) (1) 3 × 10−4 N (2) 4 × 10−4 N (3) 5 × 10−4 N (4) 6 × 10−4 N One of the following is not a property of field lines (1) Field line between a positive and a negative charge is a continuous curve without any break. (2) Two field lines cannot cross each other (3) Field lines start at positive charge and end at negative charge (4) They form closed loop 8. (1) 2σ k̂ ε0 (2) − 2σ ˆ k ε0 (3) 4σ k̂ ε0 (4) − 4σ ˆ k ε0 An electron is moving around the nucleus of a hydrogen atom lying at rest at origin in a circular orbit of radius r. The coulomb force F experienced by electron ( r is position vector of 1 electron and K = ). 4πε0 (1) − K e2 rˆ 3 (2) K e2 r r3 (4) K r (3) − K e2 r r3 e2 r3 rˆ 9. 10. The torque acting on a dipole of dipole moment P in an electric field E is (1) P.E (2) P × E (3) Zero (4) E × P 14. Let there be a spherically symmetric charge distribution with charge density varying as 5 r ρ(r ) = ρ0 − upto r = R, and ρ ( r ) = 0 4 R for r > R, where r is the distance from the origin. The electric field at a distance r (r < R ) from the origin is given by 4πρ0 r 5 r (1) − (2) 3ε0 3 R ρ0 r 5 r − 4ε0 3 R 4ρ0 r 5 r − 3ε0 4 R ρ0 r 5 r − 3ε0 4 R (3) 11. (3) (4) ρR ε0 Zero everywhere Non-zero and uniform Non-uniform Zero only at its centre 15. Electric point charges 𝐴𝐴 and 𝐵𝐵 repel each other. Electric point charges 𝐵𝐵 and 𝐶𝐶 also repel each other. If 𝐴𝐴 and 𝐶𝐶 are held close together, they will (1) Attract (2) Repel (3) Not affect each other (4) None of these 16. A thin glass rod is bent into a semicircle of radius 𝑟𝑟. A charge +Q is uniformly distributed along the upper half and a charge –Q is uniformly distributed along the lower half, as shown in Fig. The electric field 𝐸𝐸 at 𝑃𝑃, the centre of the semicircle, is The direction of electric field intensity E at a ( ) point on the equatorial line of an electric dipole of dipole moment ( p ) is (4) Perpendicular to the equatorial line and parallel to ( p ) 12. (4) A spherical portion is removed from a solid non conducting uniformly charged solid sphere as shown in the figure. The electric field inside the empty space is (1) (2) (3) (4) (1) Along the equatorial line towards the dipole (2) Along equatorial line away from the dipole (3) Perpendicular to the equatorial line and opposite to ( p ) ρr ε0 Three charges q1 = 1×10–6C, q2 = 2×10–6C and q3 = –3×10–6 have been placed as shown. Then, the net electric flux will be maximum for which of the shown gaussian surface. S2 S1 (1) S3 q1 q2 q3 (1) S1 (3) S3 13. (3) (2) S2 (4) Same for all three An insulated solid sphere of radius R has uniform charge density ρ. The electric field at a distance r from the centre of the sphere (r < R) ρr ρR (2) (1) 3ε 0 3ε 0 17. Q π ε0 r 2 2 4Q π ε0 r 2 2 (2) (4) 2Q π ε0 r 2 2 Q 4π ε 0 r 2 2 Two point charges q1 (10µC ) and q2 ( −25µC ) are placed on the x-axis at x = 1 m and x = 5 m , respectively. The electric field vector (in N/C) at 1 = 9 × 109 N − m 2 C−2 origin. Take, 4πε0 (1) −81 × 103 iˆ (3) 27 × 103 iˆ (2) 81 × 103 iˆ (4) −27 × 103 iˆ [3] 18. 19. 20. Two charges, each equal to q, are kept fixed at x = –a and x = a on the x-axis. A particle of mass q 𝑚𝑚 and charge q0 = − is placed at the origin. If 2 charge q0 is given a small displacement y(y << a) along the y-axis, the net force acting on the particle is proportional to (2) –y (1) y2 1 1 (4) – (3) 2 y y Statement 1: If a proton and an electron are placed in the same uniform electric field. They experience different acceleration Statement 2: Electric force on a test charge is independent of its mass (1) Statement 1 is True, Statement 2 is True; Statement 2 is correct explanation for Statement 1 (2) Statement 1 is True, Statement 2 is True; Statement 2 is not correct explanation for Statement 1 (3) Statement 1 is True, Statement 2 is False (4) Statement 1 is False, Statement 2 is True between q1 and q3 is F13, the ratio of magnitudes of forces F12 is x. Find x. F13 23. If the linear charge density of a cylinder is 4µCm–1 of radius 2 cm then electric field intensity at point 3.6 cm from axis is n×106 NC–1. Find n. 24. A point charge +q is placed at the centre of a cube of side a. The electric flux emerging from the cube x q . Find x. is 5 ε0 25. Four charges +Q, −Q, +Q, −Q are placed at the corners of a square taken in order. At the centre of N the square electric field is k . Find k. C 26. When the distance between two charged particles is halved, the force between them becomes x times the initial force. Find x. 27. A sample of HCl gas is placed in a uniform electric field of 3 × 104 NC−1 . The dipole moment of each HCl molecule is 6 × 10−30 Cm. The maximum torque that can act on a molecule is x × 10–26 Nm. Find x. Determine the electric dipole moment of the system of three charges, placed on the vertices of an equilateral triangle of length , as shown in the figure : 28. A square surface of side L is in the plane of the paper. A uniform electric field E , also in the plane of the paper, is limited only to the lower half of the square surface, (see figure). The electric flux associated with the square surface is xEL2 . Find x. (1) 2q ˆj (3) 2 q ˆj (2) −2q ˆj Integer Type Questions (21-30) 21. 29. A point charge q produces an electric field of magnitude 2NC–1 at a point 0.25 m from it. The x × 10−11 C. Find x. value of charge is 18 30. A cylinder of length L and radius b has its axis coincident with the x-axis (positive towards right). The electric field in this region is E = 200iˆ . The Three charges 1µC, 1µC and 2µC are kept at vertices A, B and C of an equilateral triangle ABC of side 10 cm respectively. The resultant force on the charge at C is x 3 N. Find 10 x. 22. E (4) − 3 q ˆj Three equal charges q1, q2, q3 are placed on the three adjacent corners of a square taken in that order. If the force between q1 and q2 is F12 and that flux through the left end of cylinder is yπb2. Find (y + 200). (Assume SI units) [4] SECTION-II (CHEMISTRY) Single Correct Type Questions (31-50) 31. If Raoult’s law is obeyed, the vapour pressure of the solvent in a solution is directly proportional to (1) Mole fraction of the solvent (2) Mole fraction of the solute (3) Mole fraction of the solvent and solute (4) The volume of the solution 32. What is the mole ratio of benzene (PB0 = 150 torr) and toluene (PT0 = 50 torr) in vapour phase if the given solution has a vapour pressure of 120 torr? (1) 7 : 1 (2) 7 : 3 (3) 8 : 1 (4) 7 : 8 33. At 323 K, the vapour pressure in millimeters of mercury of a methanol-ethanol solution is represented by the equation p = 120 XA + 140, where XA is the mole fraction of methanol. Then p the value of lim A is (where PA is vapour x A →1 X A pressure of A) (1) 250 mm (3) 260 mm 34. 37. The standard electrode potential for the reaction Ag+ (aq) + e– → Ag(s) Sn2+(aq) + 2e– → Sn(s) at 25°C are 0.80 volt and – 0.14 volt, respectively. The emf of the cell. Sn | Sn2+(1M) | | Ag+(1M) | Ag is: (1) 0.66 volt (2) 0.80 volt (3) 1.08 volt (4) 0.94 volt 38. The reduction electrode potential E(in V), of 0.1 M solution of M+ ions (E°RP = – 2.36 V) is: (1) –2.41 (2) +2.41 (3) –4.82 (4) +4.82 39. When two half-cells of electrode potential of E1 and E2 are combined to form a half cell of electrode potential E3, then (when n1, n2 and n3 are no. of electrons exchanged in first, second and combined half-cells) (Consider E1, E2 and E3 are reduction potentials and third half cell reaction is attained by adding 1st and 2nd half cell reaction directly). (1) E3 = E2 – E1 (2) 140 mm (4) 20 mm An aqueous solution containing 28% by mass of a liquid A (mol. mass = 140) has a vapour pressure of 160 mm at 37°C. Find the vapour pressure of the pure liquid A. (The vapour pressure of water at 37°C is 150 mm). (1) 360 mm (2) 150 mm (3) 160 mm (4) 520 mm (2) E3 = (3) E3 = 36. Azeotropic mixture are: (1) Mixture of two solids (2) Those which boil at different temperature (3) Those which can be fractionally distilled (4) Constant boiling mixtures The oxidation potential of Zn, Cu, Ag, H2 and Ni are 0.76, –0.34, –0.80, 0, 0.55 volt respectively. Which of the following reaction will provide maximum voltage? (1) Zn + Cu2+ → Cu + Zn2+ (2) Zn + 2Ag+ → 2Ag + Zn2+ (3) H2 + Cu2+ → 2H+ + Cu (4) H2 + Ni2+ → 2H+ + Ni E1n1 − E2 n2 n32 (4) E3 = E1 + E2 40. 35. E1n1 + E2 n2 n3 Which graph correctly correlates Ecell as a function of concentration for the cell Zn(s) + 2Ag+(aq) → Zn2+(aq) + 2Ag(s), Eºcell = 1.56V Y-axis: Ecell, X-axis: log10 (1) (2) (3) (4) [ Zn 2+ ] [ Ag + ]2 [5] 41. 42. Among the following, that does not form an ideal solution is(1) C6H6 and C6H5CH3 (2) C2H5Cl and C6H5OH (3) C6H5Cl and C6H5Br (4) C2H5Br and C2H5I (1) –1.02 Volt (3) + 1.02 Volt 47. W g of copper deposited in a copper voltameter when an electric current of 2 ampere is passed for 2 hours. If one ampere of electric current is passed for 4 hours in the same voltameter, copper deposited will be (in grams): (1) W (2) W/2 (3) W/4 (4) 2W 48. The ratio of weights of hydrogen and magnesium deposited by the same amount of electricity from aqueous H2SO4 and fused MgSO4 are: (1) 1 : 2 (2) 1 : 12 (3) 1 : 16 (4) None of these 49. An electrolysis of a oxytungsten complex ion using 1.10 A for 40 min produces 0.838 g of tungsten. What is the charge of tungsten in the material? (Atomic weight: W = 184) (1) 6 (2) 2 (3) 4 (4) 1 50. How many coulombs of electricity are consumed when 100 mA current is passed through a solution of AgNO3 for 30 minutes during an electrolysis experiment: (1) 108 (2) 18000 (3) 180 (4) 3000 List-I and List-II contains four entries each. Entries of List-I are to be matched with entries of List-II. List- I List- II I AlCl3, if α = 0.8 P II BaCl2, if α = 0.9 Q i = 2.8 III Na3PO4, if α = 0.9 R i = 3.8 IV K4[Fe(CN)6], if α = 0.7 S i = 3.7 (1) (2) (3) (4) i = 3.4 I-P ; II-Q ; III-S ; IV-R I-Q ; II-P ; III-S ; IV-R I-Q ; II-R ; III-P ; IV-S I-R ; II-S ; III-Q ; IV-P 43. The substance A when dissolved in solvent B shows the molecular mass corresponding to A3. The vant Hoff’s factor will be(1) 1 (2) 2 (3) 3 (4) 1/3 44. If P0 and P are the vapour pressures of a solvent and its solution with non-volatile solute respectively and N1 and N2 are the mole fractions of the solvent and solute respectively, then correct relation is: (2) P = P0N1 (1) P = P0N2 (4) P = P0(N1/N2) (3) P0 = PN1 45. If relative decrease in vapour pressure is 0.4 for a solution containing 1 mol NaCl in 3 mol H2O, NaCl is .... % ionized. (1) 60% (2) 50% (3) 100% (4) 40% 46. The standard electrode potentials of the two-half cell are given below: Ni2+ + 2e– → Ni ; E° = – 0.25 V Zn2+ + 2e– → Zn ; E° = – 0.77 V The emf of cell formed by combining the two half cells would be: (consider cell reaction to be spontaneous) (2) +0.52 Volt (4) –0.52 Volt Integer Type Question (51-60) 51. The ionization constant of a weak electrolyte is 25×10–6 while the equivalent conductance of its 0.01M solution is 19.6 S cm2 eq–1. The equivalent conductance of the electrolyte at infinite dilution (in S cm2 eq–1) will be 52. Benzene and toluene form nearly ideal solutions. At 20ºC, the vapour pressure of benzene is 75 torr and that of toluene is 22 torr. The partial vapour pressure of benzene at 20ºC for a solution containing 78 g of benzene and 46 g of toluene in torr is: 53. Density of a 2.05 M solution of acetic acid in water is 1.02 g/mL. The molality of the solution is ‘x’, then 10 x in nearest integer is: 54. Resistance of 0.1 M KCl solution in a conductance cell is 300 ohm and conductivity is 0.013 Scm–1. The value of cell constant is: (in cm–1) (nearest integer) [ 6] 55. At infinite dilution, the eq. conductances of CH3COONa, HCl and CH3COOH are 91, 426 and 391 mho cm2 eq–1 respectively at 25°C, The eq. conductance of NaCl at infinite dilution will be: 56. The weight of silver (in grams) (eq. wt = 108) displaced by that quantity of current which displaced 5600 ml. of hydrogen at STP is: 57. Electro chemical equivalent of a substance is 0.0006735; its eq. wt. is: (in grams/eq) (nearest integer) (1 F = 96500C) 58. The % of phenol dimerized in benzene if 20 g of phenol in 1 kg benzene exhibits a freezing point depression of 0.69 K. K – kg (Kf benzene = 5.12 ), (MW phenol = 94) mol (nearest integer) 59. A solution of x moles of sucrose in 100 grams of water freezes at −0.2ºC. As ice separates the freezing point goes down to –0.25ºC. How many grams of ice would have separated? 60. A solution of glucose (C6H12O6) is isotonic with 4g of urea (NH2–CO–NH2) per liter of solution. The mass of glucose in 1 litre of solution is (in grams) SECTION-III (MATHEMATICS) Single Correct Type Questions (61-80) 61. 1 2 3 2 5 4 1 2 (2) 1 1 0 3 1 0 (3) 3 −2 5 4 1 0 3 2 5 4 65. Let A and B be two symmetric matrices of order 3. Statement-1 : A(BA) and (AB)A are symmetric matrices. Statement-2 : AB is symmetric matrix if matrix multiplication of A with B is commutative. (1) Only statement-1 is true (2) Both statements are true (3) Only statement-2 is true (4) Both statements are false (4) x2 + x x −1 0 0 −2 = + then x 2 − x + 1 x 5 1 3 is equal to (1) – 1 (3) 1 63. If A is a square matrix of order 3, then the true statement is (where I is unit matrix). (1) det (–A) = –det (A) (2) det A = 0 (3) det (A + I) = 1 + det A (4) det (2A) = 2 det A A 3 × 2 matrix whose elements are given by aij = 2i – j is (1) 62. 64. (2) 0 (4) No value of x 66. cos θ sin θ B= , then B = − sin θ cos θ (1) I cos θ + J sin θ (2) I cos θ − J sin θ (3) I sin θ + J cos θ (4) − I cos θ + J sin θ Which one of the following is WRONG? (1) The elements on the main diagonal of a symmetric matrix are all zero (2) The elements on the main diagonal of a skew - symmetric matrix are all zero (3) For any square matrix A, 1 (A + AT) is 2 symmetric matrix (4) For any square matrix A, -symmetric matrix 1 (A–AT) is skew 2 0 1 1 0 If I = ,J= and −1 0 0 1 67. If A and B are square matrices of order 2, then (A + B)2 = (1) A2 + 2 AB + B2 (2) A2 + AB + BA + B2 (3) A2 + 2 BA + B2 (4) A2 + B2 [ 7] 68. 69. 70. 71. λ 1 8 5 If A = and A2 = then λ is −1 2 −5 3 equal to (1) ±3 (2) 2 (3) 3 (4) –3 Let A = [aij]n × n where aij = i2 – j2 . Then A is : (1) skew-symmetric matrix. (2) symmetric matrix (3) null matrix (4) unit matrix Let A be a 2 × 2 matrix. Statement-1 : adj(adj (A)) = A. Statement-2 : |adj A| = |A| (1) Statement-1 is true, Statement-2 is true. (2) Statement-1 is true, Statement-2 is false. (3) Statement-1 is false, Statement-2 is true. (4) Statement-1 is false, Statement-2 is false. 73. 74. 76. 77. 1 + ab + a 2b 2 1 + ac + a 2 c 2 1 + ab + a 2b 2 1 + b2 + b4 1 + bc + b 2 c 2 = 1 + ac + a 2 c 2 1 + bc + b 2 c 2 1 + c2 + c4 (a – b)2 (b – c)2 (c – a)2 2(a – b) (b – c) (c – a) 4(a – b) (b – c) (c – a) (a + b + c)3 2cot x −1 0 1 cotx −1 Let f(x) = 0 1 2cot x Column-I If A is a 3 × 3 matrix such that |5.adjA| = 5, then |A| is equal to : 1 1 (2) ± (1) ± 5 25 (3) ± 1 (4) ± 5 If A, B are two n × n non-singular matrices, then (1) AB is non-singular matrix (2) AB is singular matrix (3) (AB)–1 = A–1 B–1 (4) (AB)–1 does not exist then match 78. Column-II A π f' 2 P – 32 B π f 4 Q –4 C π f' 4 R 8 D π f 2 S 0 (1) (2) (3) (4) If A–1 = 0 (4) A is skew symmetric matrix 1 + a2 + a4 column-I with column-II a + b – x is a factor of ∆ x2 + (a + b)x + a2 + b2 – ab is a factor of ∆ ∆ = 0 has three real roots if a = b all of these 1 −1 0 −2 1 , then 0 0 −1 (1) | A | = 2 (2) A is singular matrix 0 1 / 2 −1 / 2 1 / 2 (3) Adj. A = 0 −1 0 0 −1 / 2 −4 −1 If A = , then the determinant of the 3 1 matrix (A2016 – 2A2015 – A2014) is (1) 2014 (2) 2016 (3) –175 (4) –25 (1) (2) (3) (4) −x a b Let a, b > 0 and ∆ = b − x a , then a b −x (1) (2) (3) (4) 72. 75. A Q Q P S B R P S R C P R Q Q D S S R P 2 −1 1 4 For matrices A = and B = −1 2 −1 1 which relation is true (1) (A + B)2 = A2 + 2AB + B2 (2) (A–B)2 = A2 – 2AB + B2 (3) AB = BA (4) AB ≠ BA [ 8] 79. 80. 1 0 , then P50 is: If P = 1 1 2 85. 1 0 (1) 25 1 1 25 (2) 0 1 1 0 (3) 50 1 1 50 (4) 0 1 86. Let I be an identity matrix of order 2 × 2 and 2 −1 P= . Then the value of n ∈ N for which 5 −3 P n = 5I – 8P is equal to (1) 8 (2) 12 (3) 4 (4) 6 87. 82. 88. The sum of the minors of all elements in the 1 −3 2 is –k second row of determinant 4 −1 2 3 5 2 89. If x2 + x x +1 x−2 2 x + 3x − 1 3x 3 x − 3 = ax – 12, then and 1 2 (A + cA + dI ) then the value of (d – c) 6 x2 + 2 x + 3 2x −1 2x −1 1 1 b b and B = 1 2 . If Let A = 0 1 b3 b4 10A10 + adj(A10) =B, then b1+ b2 + b3 + b4 is equal to If α, β ≠ 0 and f (n) = α n + βn and = K (1 − α) 2 (1 − β) 2 (α − β) 2 , then K is equal to 90. ‘a’ is equal to : 84. 1 0 0 0 1 0 0 0 1 3 1 + f (1) 1 + f (2) 1 + f (1) 1 + f (2) 1 + f (3) 1 + f (2) 1 + f (3) 1 + f (4) then k is 83. 1 0 0 If A = 0 1 1 , I = 0 −2 4 is The number of different possible orders of matrices having 18 identical elements is 2 5 0 0 If B is a non-singular matrix and A = 0 2 0 0 0 3 then det (B–1 AB) is equal to A–1 = Integer Type Question (81-90) 81. If for a matrix A, |A| = 6 and 1 −2 4 adj A = 4 1 1 , then k is equal to : −1 k 0 If A and B are square matrices of order 3 such that |A| = – 1, |B| = 3, then |3A2B| is equal to Let P = [aij] be a 3 × 3 matrix and let Q = [bij], where bij = 2i+jaij for 1 ≤ i, j ≤ 3. If the determinant of P is 2, then the determinant of the matrix Q is 2λ then λ is Kindly Share Your Feedback For this Paper PW Web/App - https://smart.link/7wwosivoicgd4 Library- https://smart.link/sdfez8ejd80if [ 9] ROUGH WORK