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Address : DDA Flats Kalkaji, , Physics Assignment Chapter - 1, Q1.Figure Shows Electric field lines in which an electric dipole, →, , 𝑝 is placed as shown. Which of the following Statements is, correct ?, , (A) The dipole will not experience any force., (B) The dipole will experience a force towards the right., (C) The dipole will experience a force towards the left., (D) The dipole will experience a force upwards., Q2. A point charge +q, placed at a distance d from an isolated, conducting plane. The field at a point P on the other side of the, plane is, (A) Directed perpendicular to the plane and away from the, plane., (B) Directed perpendicular to the plane but towards the, plane., (C) Directed radially away from the point charge., (D) Directed radially towards the point charge., Q3. What is the number of electric field lines of force that, radiate outwards from one coulomb of charge in vacuum ?, 11, , 11, , 10, , Q4. The electric lines of force tend to contact lengthwise and, expand laterally.What do they indicate?, (A) Repulsion between like charges and attraction between, unlike charges., (B) Attraction between like charges and repulsion between, unlike charges., (C) Only attraction between charges., (D) Only repulsion between unlike charges., Q5. The electrostatic force between two charges is a central, force. Why?, (A) Force acts along the line joining two charges?, (B) Force is the midpoint between two charges., (C) Force acts as electric field (D) Force negligible., Q6.The dielectric constant of water is 80. What is permittivity ?, (A) 7. 083 × 10, , −20, , (B) 7. 083 × 10, , ^, , Q10. An electron is separated from the proton through a, 0, , distance of 0. 53 𝐴 . Calculate the electric field at the location of, the electron., 11, , −1, , (A) 5. 1 × 10 𝑁𝐶, 9, , 9, , −1, , 10, , −1, , (B) 5. 1 × 10 𝑁𝐶, , −1, , (C)53 × 10 𝑁𝐶, (D)5. 1 × 10 𝑁𝐶, Q11. What charge would be required to electricity a sphere of, radius 25 cm so as to get surface charge density of, (A) 0.34 C, (C)1.32 C, , 3, π, , −2, , 𝐶𝑚, , ?, , (B) 0.75 C, (D)2.56 C, 0, , Q12. An electric dipole when held at 30 with respect to a, −26, , uniform electric field of 9 × 10, of the dipole., −29, , (A) 1. 8 × 10, , −29, , 𝑁𝑚. Calculate dipole moment, −26, , (B) 1. 8 × 10, , 𝐶𝑚, , −19, , (D) 18 × 10, , 𝐶𝑚, , 𝐶/𝑚, , 𝐶𝑚, , 10, , (D) 1. 15 × 10, , −10, , ^, , Q9.Two point charges of charge values Q and q are placed at, distances x and x/2 respectively from a third charge value 4q all, charges being in the same straight line. Calculate the, magnitude and nature of the charge Q, Such that the net force, experienced by the charge q is zero., (A) 3q, (B) -3q, (c) 2q (D) 4q, , (C) 18 × 10, , (A) 1. 13 × 10 (B) 3. 14 × 10, (C) 2. 13 × 10, , ^, , →, , Q8. If 𝐸 = 6𝑖 + 3𝑗 + 4𝑘 Calculate the electric flux through a, surface of area 20 units in the Y-Z plane., (A) 240 units, (B) 120 units, (C) 60 units, (D) 140 units, , 2, , −1, , −2, , (C) 70. 83 × 10, , 2, , −1, , −2, , (D) 708. 3 × 10, , 𝐶𝑁 𝑚, , 𝐶𝑁 𝑚, , −10, −10, , 2, , −1, , −2, , 2, , −1, , −2, , Q13. A charge q is situated at the centre of an imaginary, hemispherical surface, as shown in figure 2. Using Gauss's, theorem and Symmetry considerations, determine the electric, flux due to this charge through the hemispherical surface., 𝑞, 𝑞, 5𝑞, 𝑞, (A) 4Є, (B) 2Є, (C) 2Є, (D) 12Є, 0, , 0, , 0, , 0, , Q14. If an negative charge has an initial velocity in a direction, different from that an electric field, then its trajectory path will, be, (A) An ellipse (B) A Parabo (C)Circle , straight line, (D) Depends upon how heavy particle is, Q15.The value of electric permittivity of free space is, 9, , (A) 9 × 10, , (B) 8. 85 × 10, , 2, , 𝐶𝑀, −12, , (C) 8. 85 × 10, , 2, , −12 𝑁𝑀, , 𝑁, 2, , 2, , sec, , 𝐶, 2, , 9, , 𝐶, , 2, , 𝑁 𝑀, , (D) 9 × 10, , 2, , 𝐶, , 2, , ., , 𝑁𝑀, , 𝐶𝑁 𝑚, , 𝐶𝑁 𝑚, , Q7. An arbitrary surface encloses a dipole. What is the electric, flux through this surface 2?, , Q16. If two point charge separated by a fixed distance , +Q> +q, ,then electric field between the charge will be zero at, (A) Closer to +Q (B) Closer to +q, (C) Exactly at midpoint

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(A) 6Є, , (B) 0, , (C) Double, , (D) 2Є, , (D) Electric field cannot be zero; it is the property of charge., , Q17. A Charge to divide into two partsQ and (Q-q) , then ratio of, 𝑄, if they have maximum force between them when separated, 𝑞, by some distance r.Then find the ratio, (A) 1:4, , (B) 3:4, , (C) 1:2, , 𝑄, 𝑞, , (D) 2:1, , Q18.SI Unit of permittivity of free space is :, 2, , −1, , −2, , (A) Farad (B) Weber (C) 𝐶 𝑁 𝑚, , 2, , −2, , (D) 𝐶 𝑚, , 19, , Q29. When 10 electrons are removed from a neutral platel, the, electric charge on it is, +19, , Q19.The unit of electric dipole moment is, (A) Newton (B) Coulomb (C) Farad (D) debye, Q20. Which of the following statements is not true about, Gauss’s law?, (A) Gauss’s law is true for any closed surface., (B) The term q on the right side of Gauss’s law includes, the sum of all charges enclosed by the surface., (C) Gauss’s law is not very useful in calculating, electrostatic fields when the system has some, symmetry., (D) Gauss’s law is based on the inverse square dependence, on distance contained in the coulomb’s law., Q21.The surface considered for Gauss’s law is called :, (A) Closed surface, (B) Spherical surface, (C) Gaussian surface, (D) Plane surface, Q22. What will happen when we rub a glass rod with silk cloth ?, (A) Some of the electrons from the glass rod are transferred to, the silk cloth., (B) The glass rod gets positive charge and silk cloth gets, negative charge., (C) New Charge is created in the process of rubbing., (D) both (A) and (B) are correct., Q23. When a person combs his hair, static electricity is, sometimes generated by what process ?, (A) contact between the comb and hair results in a charge., (B) Friction between the comb and hair results in the transfer, of electrons., (C) Deduction between the comb and hair., (D) Induction between the comb and hair., Q24. Two charged spheres are separated by 2 mm. Which of the, following would yield the greatest attractive force ?, (A) + 2𝑞 𝑎𝑛𝑑 − 2𝑞 (B) + 2𝑞 𝑎𝑛𝑑 + 2𝑞 (C) − 2𝑞 𝑎𝑛𝑑 − 2𝑞 (D), − 1𝑞 𝑎𝑛𝑑 − 4𝑞, Q25.A cylindrical conductor is placed near another positively, charged conductor the net charge acquired by the cylindrical, conductor will be, (A) positive only (B) negative only, (C) zero (D) either positive or negative, Q26. A comb run through one dry hair attracts small bits of, paper.This is due to, (A) comb is a good conductor (B) paper is a good conductor., (C) the atoms in the people get polarized by the charge comb., (D) the comb possesses magnetic properties., Q27. A conducting sphere is negatively charged. Which of the, following statements is true ?, (A) the charge is uniformly distributed throughout the entire, volume., (B) the charge is located at the centre of the sphere., (C) the charge is located at the bottom of the sphere because of, gravity., , (A) − 1. 6 𝐶 (B) + 1. 6 𝐶 (C) 10, , −19, , 𝐶(D) 10, , 𝐶, 13, , Q30.A body has a charge of − 2µ𝐶.If it has 2. 5 × 10 protons ,, then how many electrons the body has ?, 13, , 13, , (A) 1. 25 × 10 (B) 2. 5 × 10, , 13, , (C) 3. 75 × 10, , (D) None of these, , Q31. In the process of charging the mass of the negatively, charged body, (A) increases (B) decreases (C) remains constant, (D) is not related to the charging process, Q32. An object is charged when it has charge imbalance which, means the, (A) object contains no protons (B) object contains no electrons, (C) object contains equal number of electrons and protons, (D) object contains an unequal number of electrons and protons, Q33. A polythene piece rubbed with wool is found to have a, −7, , negative charge of 6 × 10 𝐶. The number of electrons, transferred to polythene from wool is, 10, , (A) 3. 75 × 10, , 10, , 12, , 12, , (B) 9. 6 × 10 (C) 9. 6 × 10 (D) 3. 75 × 10, , Q34.For Coulomb force to be operative the least size of atom, will be, −12, , (A) 10, , −15, , 𝑚(B) 10, , −10, , 𝑚(C) 10, , −8, , 𝑚 (D) 10 𝑚, , Q35. Two point charges of + 3µ𝐶and + 4µ𝐶repel each other with, a force of 10 N. if each is given an additional charge of − 6µ𝐶,, the new force is, (A) 2 N (B) 4 N (C) 5 N (D) 7.5 N, Q36. The ratio of magnitude of electrostatic force and, gravitational force of an electron and proton is, 39, , 39, , (A) 6. 6 × 10 (B) 2. 4 × 10, , 29, , (C) 6. 6 × 10, , 29, , (D) 2. 4 × 10, , Q37. The electrostatic attracting force on small square of charge, 0. 2µ𝐶due to another small sphere of charge 0. 4µ𝐶in air is 0.4 N., The distance between the two square is, −6, , −3, , −3, , (A) 43. 2 × 10 𝑚(B) 42. 4 × 10 𝑚(C) 18. 1 × 10 𝑚(D), −6, , 19. 2 × 10 𝑚, Q38. Four charges are arranged at the corner of a square ABCD, as shown in the figure. The force on the charge kept at the, centre O is, (A) zero, (B) along the diagonal BD, (C) along the diagonal AC, (D) perpendicular to side AR, Q39. Two charges q and -3q are fixed on x-axis separated by a, distance d. where should a third charge 2q be placed from A, such that it will not experience any force, , (A), , 𝑑− 3𝑑, 2, , (B), , 𝑑+ 3𝑑, 2, , (C), , 𝑑+3𝑑, 2, , (D), , 𝑑−3𝑑, 2

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(D) the charge is uniformly distributed on the surface of the, sphere., Q28. Charge on a body is integral multiple of, ± 𝑒 .it implies the law of, (A) conservation of charge (B) conservation of mass, (C) conservation of energy (D) quantization of charge, , Q40. A Charge Q is placed at the centre of the line joining two, point charges +q and + q as shown in the figure (system in, equilibrium). The ratio of the charges Q and q is, , (A) 4 (B), , 1, 4, , (C) -4 (D), , −1, 4, , Q41. Four point charges are placed at the corner of a, square ABCD of side 10 cm as shown in, figure. The force on a charge1µ𝐶 placed at, the centre of square is, (A) 7 N (B) 8 N (C) 2 N (D) Zero, Q42. The physical quantity that has the unit Newton/coulomb, is, (A) electric charge (B) electric force, (C) electric field (D) electric potential, Q43. A proton moving at constant velocity enters, the region between two charges plates as show, in figure which of the path Shown indicates the, proton’s trajectory leaving the region between, the charge plates ?, , Q53. Deuteron and Alpha particles in air are at separation 1, 0, , 𝐴 . The magnitude of electric field intensity on Alpha particle, due to deuteron is, 11, , −1, , 11, , −1, , 11, , −1, , (A) 5. 76 × 10 𝑁𝐶 (B) 1. 44 × 10 𝑁𝐶 (C) 2. 828 × 10 𝑁𝐶 (D), Zero, Q54.Two charges + 5µ𝐶and + 10µ𝐶 are placed 20cm apart. The, electric field at the midpoint between the two charges is, 6, , (A) 4. 5 × 10 𝑁/𝐶 𝑡𝑜𝑤𝑎𝑟𝑑𝑠 + 5µ𝐶, , (B), , 6, , 13. 5 × 10 𝑁/𝐶 𝑡𝑜𝑤𝑎𝑟𝑑𝑠 + 5µ𝐶, 6, , (C) 4. 5 × 10 𝑁/𝐶 𝑡𝑜𝑤𝑎𝑟𝑑𝑠 + 10µ𝐶 (D), 6, , 13. 5 × 10 𝑁/𝐶 𝑡𝑜𝑤𝑎𝑟𝑑𝑠 + 10µ𝐶, , (A)A, , (B) B, , (C) C, , Q55. Two small charged spheres A and B have charges 10µ𝐶and, 40µ𝐶respectively and are held at a separation of 90 cm from, each other. At what distance from an electric intensity would be, zero ?, (A) 22.5 cm (B) 18 cm (C) 36 cm (D) 30 cm, , (D) D, , Q44. Force per unit charge is known as, (A) electric flux (B) electric field, (C) electric potential (D) electric current, Q45. The electric field at the point is, (A) always continuous, (B) continuous if there is no charge at the point, (C) discontinuous if there is a charge at that point, (D) both B) and C are correct, Q46. The dimensional formula of electric intensity is, , [, , 1 1 3 −1, , (A) 𝑀 𝐿 𝑇 𝐴, , ] (B) [𝑀1𝐿−1𝑇−3𝐴−1] (C) [𝑀1𝐿1𝑇−3𝐴−1] (D) [𝑀1𝐿2𝑇1𝐴−1], , Q47. The charge on a object is doubled the electric field, becomes, (A) half (B) double (C) unchanged (D) thrice, −4, , Q48. A force 2.25 N acts on a charge of 15 × 10, of electric field at the point is, −1, , −1, , −1, , 𝐶.The intensity, , −1, , (A) 150 𝑁𝐶 (B) 15 𝑁𝐶 (C) 1500 𝑁𝐶 (D) 1. 5 𝑁𝐶, Q48. A force 2.25 N acts on a charge of, −4, , 15 × 10, , 𝐶.The intensity of electric field at the point is, −1, , −1, , −1, , −1, , (A) 150 𝑁𝐶 (B) 15 𝑁𝐶 (C) 1500 𝑁𝐶 (D) 1. 5 𝑁𝐶, , Q49.The electric field required to keep a water drop of mass ‘m’, just to remain suspended when charged with one electron is, 𝑚𝑔, 𝑒𝑚, (A) mg, (B) 𝑒, (C) emg, (D) 𝑔, Q50.A Charge of magnitude 3e and mass 2m is moving in an, →, , electric field 𝐸 the acceleration imparted to the charges is, , Q56. If σ = Surface charge density, ϵ = electric permittivity,, σ, the dimension of ϵ are same as, (A) electric force (B) electric field intensity, (C) pressure (D) electric charge, Q57. Four metal conductors having different shapes :, 1. A sphere 2. Cylinder 3. Pear 4. Lighting conductor, are mounted on insulating stands and charged. The one which, is the best suited to retain the charges for a longer time is, (A) 1 (B) 2 (C) 3 (D) 4, Q58.Out of the following is not a property of field lines, (A) Field lines are continuous curves without any breaks, (B) Two field lines cannot cross each other, (C) Field lines start at positive charges and end at negative, charges, (D) They form closed loops, Q59. Electric field lines contract lengthwise it shows, (A) repulsion between same charges, (B)attraction between opposite charges, (C) no relation between force and contraction, (D) electric field lines do not move on straight path, Q60. Which of the following figures represents the electric field, lines due to single positive charge ?

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(A), , 2𝐸𝑒, 3𝑚, , 3𝐸𝑒, 2𝑚, , (B), , (C), , 2𝑚, 3𝐹𝑒, , (D), , 3𝑚, 2𝐸𝑒, , Q51. A particle of mass m and charge q is placed at rest in, uniform electric field and then released the kinetic energy, obtained by the particle after moving a distance y will be, 2, , 2, , 2, , (A) 𝑞 𝐸𝑦(B) 𝑞𝐸𝑦(C) 𝑞𝐸 𝑦(D) 𝑞𝐸𝑦, , Q52. A charged particle of mass m and charge q initially at rest, is released in an electric field of magnitude is its kinetic energy, after time t will be, (A), , 2 2, , 2𝐸 𝑡, 𝑚𝑞, , (B), , 2 2 2, , 𝐸𝑞𝑡, 2𝑚, , (C), , 2, , 𝐸 𝑞𝑚, 2, , 2𝑡, , (D), , Q61. Which of the following Figures correctly shows the top of, view sketch of the electric field lines for a uniformly + charged, hollow cylinder as shown in figure ?, , 𝐸𝑞𝑚, 2𝑡, , Q64. A circular plane sheet of radius 10 cm is placed in a, 5, , −1, , 0, , uniform electric field of 5 × 10 𝑁𝐶 making an angle of 60 with, the field. The electric flux through the sheet is, 2, , 2 −1, , 4, , 2 −1, , (A) 1. 36 × 10 𝑁𝑚 𝐶 (B) 1. 36 × 10 𝑁𝑚 𝐶, 2, , 2 −1, , 4, , 2 −1, , (C) 0. 515 × 10 𝑁𝑚 𝐶 (D) 0. 515 × 10 𝑁𝑚 𝐶, 3, , −1, , Q65. A uniform electric field 𝐸 = 2 × 10 𝑁𝐶 is acting along, the positive x-axis. The flux of this field through the square of, 10 cm on a side whose plane is parallel to the y-z plane is, −1, , 2, , −1, , 2, , −1, , 2, , −1, , 2, , (A) 20 𝑁𝐶 𝑚 (B) 30 𝑁𝐶 𝑚 (C) 10 𝑁𝐶 𝑚 (D)40 𝑁𝐶 𝑚, , Q66. What will be the values of the electric field at the centre of, the electric dipole, (A) zero, (B) equal to the electric field due to one charge at the centre, (C) Twice the electric field due to one charge at centre, (D) half the value of electric field due to one charge at centre, Q67. If r is the distance of a point from the centre of a short, dipole, then the electric field intensity due to the short dipole, remains proportional to, 2, , 3, , −2, , (A) 𝑟 (B) 𝑟 (C) 𝑟, , −3, , (D) 𝑟, , Q68. An electric dipole coincides on the Z-axis and its midpoint, is at the origin of the coordinate system. The electric field at an, axial point at a distance from origin is 𝐸𝑧and electric field at an, equatorial point at a distance y from origin 𝐸𝑦. Here z = y >> a ,, so, , |𝐸𝑧|, |𝐸𝑦|, , is equal to, , (A) 1 (B) 4 (C) 3 (D) 2, →, , Q69. An Electric dipole of moment 𝑝 is placed in uniform, →, , electric field 𝐸 .The maximum torque experienced by the dipole, is, →, , →, , (A) pE (B) p/E (C) E/p (D) 𝑝 .𝐸, , −10, , Q70. Two equal and opposite charges 2 × 10 𝐶are placed at a, distance of 1 cm, forming a dipole and are placed in an electric, , Q62. The SI Unit of electric flux is, −1, , 2, , −2, , (A) 𝑁𝐶 𝑚 (B) 𝑁𝐶 𝑚, , −2, , 2, , −1, , −2, , (C) 𝑁𝐶 𝑚 (D) 𝑁𝐶 𝑚, , Q63. The dimensional formula of electric flux is, , [, , −1 1 −2, , (A) 𝑀 𝐿 𝑇, , ] (B) [𝑀1𝐿3𝑇−3𝐴−1](C) [𝑀2𝐿2𝑇−2𝐴−2](D) [𝑀1𝐿−3𝑇3𝐴1], , →, , →, , Q74. If ∮𝑠𝐸 . 𝑑𝑠 = 0 over a surface then, (A) the electric field inside the surface and on it is zero., (B) the electric field inside the surface is necessary uniform, (C) all changes must necessarily be outside the surface., (D) all of these, Q75. Four charges + 8𝐶, − 3𝐶, + 5𝐶 𝑎𝑛𝑑 − 10𝐶 are kept inside a, closed surface. What will be the outgoing flux through the, surface ?, (A) 26 Vm (B) 0 Vm (C) 10 Vm (D) 8 Vm, Q76. A point charge is 4µ𝐶at the centre of a cubic Gaussian, surface 10 cm on edge. Net electric flux through the surface is, 5, , 2 −1, , (B) 4. 5 × 10 𝑁𝑚 𝐶, , 6, , 2 −1, , (D) 2. 5 × 10 𝑁𝑚 𝐶, , (A) 2. 5 × 10 𝑁𝑚 𝐶, , (C) 4. 5 × 10 𝑁𝑚 𝐶, , 5, , 6, , 2 −1, 2 −1, , Q77. Gauss’s Law is valid for, (A) any closed surface (B) only regular closed surfaces., (C) any open surface (D) only irregular open surfaces., , 5, , field of 2 × 10 𝑁/𝐶. The maximum torque on dipole is, −6, , 8, , −9, , (A) 2 2 × 10 𝑁𝑚 (B) 8 × 10 𝑁𝑚 (C) 4 × 10 𝑁𝑚 (D), −7, , 4 × 10 𝑁𝑚, Q71. The frequency of oscillation of an electric dipole having a, dipole moment p and rotational inertia i, oscillating in a, uniform electric field E is given by, (A) (𝑖/2π) 𝑖/𝑝𝐸(B) (𝑖/2π) 𝑝𝐸/𝑖 (C) (2π) 𝑝𝐸/𝑖 (D) (2π) 𝑖/𝑝𝐸, 0, , Q72. An electric dipole is placed at an angle of 30 with an, 5, , −1, , electric field of intensity 2 × 10 𝑁𝐶 . It experiences a torque, equal to 4 Nm. The charges on the dipole if the dipole length is, 2 cm is, (A) 8 mC (B) 4 mC (C) 6 mC (D) 2 mC, Q73. In a certain region of space the electric field is along the, z-direction throughout. The magnitude of vector field is, however not constant but increased uniformly along the, 5, , −1, , −1, , z-direction at a rate of 10 𝑁𝐶 𝑚 . The force experienced by, , Q78. Which of the following statements is not true about, Gauss’s Law ?, (A) Gauss’s Law is true for any closed surface, (B) the term on the right side of go slow includes the sum of all, charges enclosed by surface., (C) Gauss’s Law is not very useful in calculating electrostatic, fields when the system has some symmetry ., (D) Gauss’s Law is based on the inverse square dependence on, distance content in the plants lo, →, , →, , Q79. If ∮𝑠𝐸 . 𝑑𝑠 = 0 , inside a surface , that means there is, (A) no net charge present inside the surface, (B) uniform electric field inside the surface, (C) discontinuous field lines inside the surface, (D) some charges present inside the surface, Q80. For a given surface the Gauss’s Law is stated as, →, , →, , ∮𝑠𝐸 . 𝑑𝑠 = 0 . From this we can conclude that, (A) E is necessary zero on the surface

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−7, , system having a total dipole moment equal to 10 𝐶𝑚 in the, negative z-direction is, −2, , −2, , −4, , −4, , (A) − 10 𝑁 (B) 10 𝑁(C) 10 𝑁 (D) − 10 𝑁, Q74. Which quantity is a vector quantity among the following ?, (A) electric flux, (B) electric charge, (C) electric field, (D) electric potential, Q86. A conducting sphere of radius K = 20 cm is given a charge, 𝑄 = 16µ𝐶. What is E at its centre?, 6, , 6, , 6, , (A) 3. 6 × 10 𝑁/𝐶 (B) 3. 6 × 10 𝑁/𝐶(C) 𝑧𝑒𝑟𝑜 (D) 0. 9 × 10 𝑁/𝐶, Q87.Two large thin metal plates are parallel and close to each, other on their inner faces the plates have service charges, −22, , densities of opposite signs and magnitude 27 × 10, electric field E in region II in between the plates, , −2, , 𝐶𝑚 .The, , −8, , (A) 4. 25 × 10 𝑁/𝐶, 𝑁/𝐶, , −10, , (C) 3. 05 × 10, , 𝑁/𝐶, , −10, , (D) 5. 03 × 10, , 𝑁/𝐶, , Q88. A point charge + 20µ𝐶 is at distance 6 cm directly above, the centre of a square of side 12 cm as shown in figure. The, magnitude of electric flux through the square is, 6, , 2 −1, , 5, , 2 −1, , 5, , 2 −1, , 6, , 2 −1, , (A) 2. 5 × 10 𝑁𝑚 𝐶, , (B) 3. 8 × 10 𝑁𝑚 𝐶, , −2, , −2, 3, , −1, , −2, , (C) 632 × 10 𝑁𝑚 𝐶 (D) 632 × 10 𝐶𝑁 𝑚, , Q90. The electric field components in the given figure are, 1/2, , −1, , −1/2, , , 𝐸𝑦 = 𝐸𝑧 = 0in whichα = 800 𝑁𝐶 𝑚, , . The charge, −2 −1, , within the cube is net flux through the cube is 1. 05 𝑁𝑚 𝐶, (assume α = 0. 1 𝑚), −12, , 12, , −12, , 𝐶(B) 9. 27 × 10 𝐶(C) 6, 97 × 10, , 𝐶(D), , 12, , 6. 97 × 10 𝐶, , Q91.The total flux through the faces of the cube with side of the, length a if a charge q is placed at A corner of the cube is, , (A), , 𝑞, 8𝑒0, , (B), , 𝑞, 4𝑒0, , (C), , 𝑞, 2𝑒0, , πϵ0𝑅, , (D), , πϵ0𝑅, , 2πϵ0𝑅, , Q85. What is the net charge on a conducting sphere of radius 10, cm ? Given that the electric field 15 cm from the centre of the, , −9, , 2 −1, , (A) 9. 27 × 10, , Q84. Two parallel infinite line charges +λ and − λare placed, with a separation distance R are in a free space. The net electric, field is exactly midway between the two line charges is, 2λ, λ, λ, (A) zero (B), (C), (D), , 7. 5 × 10 𝐶, , 3, , 𝑟, , −9, , −5, , (A) − 7. 5 × 10 𝐶(B) − 7. 5 × 10 𝐶(C) 7. 5 × 10 𝐶(D), , (A) 10 𝑁𝑚 𝐶 (B) 10 𝐶𝑁 𝑚, , 𝐸𝑥 = 𝑎𝑥, , 𝑟, , 3, , Q89. The electric flux for Gaussian Surface A that encloses the, charged particle in free space is, ( Given 𝑞1 = − 14 𝑛𝐶 , 𝑞2 = 78. 85 𝑛𝐶, 𝑞3 =− 56 𝑛𝐶), , 3, , Q83. According to Gauss’s Law, electric field of an infinitely long, straight wire is proportional to, 1, 1, 1, (A) r (B) 2 (C) 3 (D), , −5, , (D) 2. 9 × 10 𝑁𝑚 𝐶, , 2 −1, , Q82. Charge on a conducting metal sphere is present, (A) on the surface of sphere, (B) inside the sphere, (C) outside the sphere, (D) both inside and outside of sphere, , square is equal to 3 × 10 𝑁/𝐶 and its directed inward, , (C) 4. 2 × 10 𝑁𝑚 𝐶, , 3, , Q81. Charge q is first kept in a sphere of radius 5 cm and then it, is kept in a cube of side 5 cm. The outgoing flux, (A) will be more in a case of sphere, (B) will be more in case of cube, (C) will be same in both cases, (D) cannot be determined, , 𝑟, , −10, , (B)6. 28 × 10, , (B) E is perpendicular to the surface at every point, (C) the total flux through the surface is zero, (D) the flux is only going out the surface, , 𝑞, 𝑒0, , Q92. Three charges of equal magnitude q is placed at the, vertices of a equilateral triangle of the side l the force on a, charge Q placed at the centroid of the triangle is

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(A), , 3𝑄𝑞, 2, , 4π𝑒0𝑙, , (B), , 2𝑄𝑞, 2, , 4π𝑒0𝑙, , (C), , 𝑄𝑞, 2, , 2π𝑒0𝑙, , (D) 𝑍𝑒𝑟𝑜, , Q93. Four charged particles are placed at the vertices of a, square as shown in the figure an electron that is free to move is, placed at the exact centre of the square. In which direction will, electron move ?, (A) it will move toward A, (B) it will move toward B, (C) it will move toward C, (D) it will move toward D, , Q94. Four charges as shown in the figure are placed at the, corner of a square of side length a. What is the ratio of (Q/q) if, net force on Q is zero ?, 1, (A), 2 2, , (B) − 2 2, 1, (C) 2, (D), , 1, 2, , Q95. 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 net force acting on each, charge is, 𝐹, 𝐹, 𝐹, (A) 8 (B) 4 (C) 4F (D) 16, Q96. Each of two point charges are the doubled and their, distance is half force of interaction becomes n times , where n, is, (A) 4 (B) 1 (C) 18 (D) 16, Q97. The minimum value of force acting between two point, charges placed 1 m apart from one another is, (A), , 2, , 𝑘𝑒, 𝑘𝑒, , (B) 𝑘𝑒 (C), , 𝑘𝑒, 4, , (D), , 2, , 𝑘𝑒, 2, , Q98. A and B are two identical spherical charged bodies which, repel each other with a force F, kept at a final distance. A third, uncharged sphere of the same size is brought in contact with, the sphere and removed. It is then kept at midpoint of A and B., Find the magnitude of force on C., 𝐹, 𝐹, (A) 2 (B) 8 (C) F (D) Zero, Q99.Figure shows the electric field lines around three point, charges A, B and C. Which of the following charges are positive, ?, (A) only A (B) Both A and C (C) Only C (D) Both B and C, , Q100. In Question 99 , Which charge has the largest magnitude, ?, (A) A (B) B (C) C (D) B and C have equal magnitude