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1. The gravitational force between two stones of mass 1 kg each separated by a distance of 1 meter in vacuum is (a) 6.675 × 10^-5 newton (b) 6.675 × 10^-11 newton (c) 6.675 × 10^-8 newton (d) zero.

2. Circuit shown in the figure below contains two diodes each with a forward resistance of 50 ohm add with infinite backward resistance. If the battery voltage is 6V, then current through 100 ohm resistance is (a) 0.02 A (b) 0.03 A (c) 0.036 A (d) 0.0 A.

3. A rod is moving with speed 0.8 c with respect to observer O. The percentage contration in the length as observed by observer O is (a) 40% (b) 16% (c) 20% (d) 36%.

4. A perfect gas goes from a state A to another state B by absorbing 8 × 10⁵ J of heat and doing 6.5 × 10⁵J of external work. It is now transferred between the same two states in another process in which it absorbs 10⁵ J or heat> in the second process (a) work done by gas is 10⁵ J (b) work done on gas is 10⁵ J (c) work done by gas is 0.5 × 10⁵ J (d) work done on the gas is 0.5 × 10⁵J.

5. A stable nucleus having radius half that of Fe-56 is (a) Ca-40 (b) Li-7 (c) Na-21 (d) S-16.

6. A force of 2 newton acting on a certain mass for 6 second gives it a velocity of 6 m s^-1. The mass is equal to (a) 2 kg (b) 4 kg (c) 1 kg (d) 0.5 kg.

7. A current of 10^-5 A produces a deflection of 10° in a moving coil galvanometer. A current of 10^-6 A produces, in the same galvanometer a deflection of (a) 0.1° (b) 1° (c) (d) 10°.

8. Two bodies with masses m₁ and m₂ (m₁ > m₂) are joined by a string passing over a fixed pulley. The centres of gravity of the two masses are initially at the same height. Assume masses of the pulley and weight of the thread negligible. The acceleration of the centre of mass of m₁ and m₂, is (a) (b) (c) (d) .

9. A body of mass m_,having momentum p is moving on a rough horizontal surface. If it is stopped in a distance x, the coefficient of friction between the body and the surface is given by (a) (b) (c) (d) .

10. A particle of mass m and charge +q is placed at rest in a uniform electric field and released. The kinetic energy it attains after moving a distance y along the field is (a) qE²y (b) m(qEy) (c) qEy (d) qEy.

11. A small steel ball falls through a syrup at a constant speed of 10 cm/s. If the steel ball is pulled upwards with a force equal to twice its effective weight, how fast will it move upward ? (a) 20 cm/s (b) 3 m/s (c) 5 cm/s (d) 10 cm/s.

12. A sphere of radius 1 cm has potential of 8000 V. The energy density near the surface of sphere will be (a) 2.83 J/m³(b) 32 J/m³ (c) 8 × 10³ J/m³ (d) 64 × 10⁵ J/m³.

13. Two spherical conductors A₁ and A₂ of radii r₁ and r₂ and carrying charges q₁ and q₂ are connected in air by a copper wire. Then the equivalent capacitance of the system is (a) 4pÎ₀(r₁+r₂) (b) 4pÎ₀r₁(c) 4pÎ₀r₂ (d) 4 pÎ₀r₁r₂/(r₂ ?r₂).

14. A beam of sound is 10⁶ times as intense as that with minimum audible intensity. The intensity of the beam is thus (a) 0.6 dB (b) 6 dB (c) 60 dB (d) 10⁶ dB.

15. The ratios L/R and R C(L= inductance, R = resistance and C = capacitance) have the dimensions as those of (a) acceleration (b) velocity (c) force (d) time.

16. If the end of a metal rod is heated, then the rate of flow of heat does not depend upon (a) area of the end of the rod (b) temperature gradient (c) mass of the rod (d) time.

17. Consider the situation shown in figure. The wire AB is slid on fixed rails with a constant velocity. If the wire AB is replaced by semi-circular wire, the magnitude of induced emf will

(a) increase or decrease depending on whether the semi-circle buldges towards the resistance or away from it (b) remain the same (c) increase (d) decrease.

18. Above Curie temperature a ferromagnetic substance becomes (a) diamagnetic (b) super conductor (c) paramagnetic (d) strongly ferromagnetic.

19. A particle executes simple harmonic motion along a straight line with an amplitude A. The potential energy is maximum when the displacement (a) ± A/Ö2 (b) ± A/2 (c) zero (d) ± A.

20. If mass of an electron be m, charge e and radius of its orbit r in an atom and the corresponding angular momentum L, then the magnetic moment equals to (a) eL (b) (c) (d) .

21. At what angle does a diver see the setting sun ? (a) at 60° to the horizon (b) at 41° to the horizon (c) at 49° to the horizon (d) at 90° to the horizon.

22. Neon nucleus absorbs energy and decays into a nucleus X emitting two a-particles. Then unknown nucleus X is (a) Boron (b) Nitrogen (c) Oxygen (d) Carbon.

23. A slide projector forms an image 3.5 m high of an object 35 mm in height. The illumination of the object and the image will be in the ratio (a) 10³ : 1 (b) 10⁴ : 1 (c) 1 : 10⁴ (d) 1 : 10² .

24. Two plane mirrors are at right angles to each other. A man stands between them and combs his hair with his right hand. In how many of the images will he be seen using his right hand ? (a) 1 (b) None of the other three choices given here (c) 3 (d) 2.

25. The wavelength of K_a- X-rays produced in an X-ray tube is 0.76 Å. The atomic number of the anode material of the tube is (a) 42 (b) 41 (c) 40 (d) 38.

26. The coils of a step down transformer have 500 and 5000 turns. In the primary coil an AC of 4 A at 2200 volts is sent. The value of the current and potential difference in the secondary will be (a) 40 A, 220 V (b) 40 A, 22,000 V (c) 0.4 A, 22,000 V (d) 20 A, 220 V.

27. A body of mass M moving with a speed v undergoes a head-on collision with a body of mass m moving with the same velocity but in opposite direction. If the two body stick together after the collision, the speed of the composite body will be (a) (b) v/2 (c) (d) zero.

28. The angular velocity of a body changes from w₁ to w₂ without applying torque but by changing moment of inertia. The ratio of initial radius of gyration to the final radius of gyration is (a) 1/w₂ : 1/w₁ (b) Öw₂ : Öw₁ (c) w₁ : w₂ (d) w₂² : w₁².

29. An inclined plane makes an angle of 30° with the horizontal. A solid sphere rolling down this inclined plane from rest without slipping has a linear acceleration equal to (a) 5g/14 (b) 5 g/7 (c) 2 g/3 (d) g/3.

30. A ball of mass m is dropped from height h on a platform fixed at the top of a vertical spring. the plateform is depressed by a distance x. What is the spring constant ?

(a) 2 m g h/x² (b) 2m g/x (c) 2 mg (h + x)h²(d) 2 mg (h+ x)/x².

31. The Young's modulus of the material of a wire is 6 × 10¹² N m^-2 and there is no transverse strain in it, then its modulus of rigidity will be (a) 3 × 10¹² N m^-2 (b) None of the other three choices given here (c) 2 × 10¹² N m^-2 (d) 10¹² N m^-2.

32. When a body is taken from equator to the poles, its weight (a) increases at North pole and decreases at South pole (b) remains the same (c) increases (d) decreases.

33. A hole in a p-type semi-conductor is (a) a missing atom (b) an excess electron (c) a missing electron (d) a donor level.

34. For a given plate voltage the plate current in a triode valve is maximum when the potential of (a) The grid is positive and plate is negative (b) The grid is negative and plate is positive (c) The grid is less positive and plate is more positive (d) The grid is zero and plate is positive.

35. The diagram given below represents an area A = 0.5 m² situated in a uniform magnetic field B = 4.0 weber/m² with its normal making an angle of 60° with respect to magnetic field. The value of magnetic flux through the area will be equal to (a) weber (b) 2.0 weber (c) 3^1/2 weber (d) 1.0 weber.

36. Which one of the following statements does not hold good when two balls of masses m₁ and m₂ undergo elastic collision ? (a) when m₁ < m₂ and m₂ at rest, there will be maximum transfer of momentum (b) when collision is oblique and m₂ at rest with m₁ = m₂, after collisions the ball moves in opposite direction (c) when m₁ = m₂ at rest, there will be maximum transfer of K.E (d) when m₁ > m₂ and m₂ moves with four times the velocity of m₁.

37. When two air babbles of radii 4 cm and 6 cm respectively are in contact, the radius of common surface is (a) 12 cm (b) 6 cm (c) 4 cm (d) 72 cm.

38. For a transistor in C-E configuration, b = 50 and potential drop across the collector is 2 V. If resistance of 2K is there in the collector circuit then base current will be (a) 50 mA (b) 20 mA (c) 25 mA (d) 40 mA.

39. An unpolarised beam of transverse waves is one whose vibrations (a) are confined to a single plane (b) occur in all directions perpendicular to the direction of propagation (c) occur in all directions (d) have not passed through a polaroid disc.

40. The greatest acceleration or deceleration that a train may have is a. The minimum time in which the train can get from one station to the next at a distance s is (a) (b) (c) (d) .

41. Three plates A, B, C each of area 50 cm² have separation 3 mm between A and B and 3 mm between B and C. The energy stored when the plates are fully charged is

(a) 2 nJ (b) 7 nJ (c) 5 nJ (d) 1.6 nJ.

42. The resistance of a heater coil is 110 ohm. A resistance R is connected in parallel with it and the combination is joined in series with a resistance of 11 ohm to a 220 volt main line. The heater operates with a power of 110 watt. The value of R in ohm is (a) negative (b) 12.22 (c) 24.42 (d) that the given values are not correct.

43. Which of the following diagrams shows correctly the dispersion of white light by a prism ? (a)

(b)

(c)

(d)

.

44. The escape velocity of a body from the surface of Earth is 11.2 km s^-1. If a body is projected in a direction making an angle of 45° to the vertical, then the escape velocity is (a) 7.2 km s^-1 (b) 6.2 km s^-1 (c) 2.11 km s^-1 (d) 11.2 km s^-1.

45. Consider the system shown in figure

pulley and the string are light and all the surfaces are frictionless. The tension in the string is (take g = 10 m/s²) (a) 5 N (b) 1 N (c) 0 N (d) 2 N.

46. A stone is thrown with a velocity v at an angle q with the horizontal. Its speed when it makes an angle b with the horizontal is (a) (b) a cos q (c) (d) v cos q cos b.

47. Joule × sec is the unit of (a) momentum (b) energy (c) power (d) angular momentum.

48. Some equipotential surfaces are shown in figure. Then the electric field strength will be

(a) 50 V/m at an angle 120° with X-axis (b) 200 V/m at an angle 120° with X-axis (c) 100 V/m along Y-axis (d) 100 V/m along X-axis.

49. A cylindrical tube open at both ends, has a fundamental frequency n. If one of the ends is closed, the frequency becomes/remains (a) 0.5 n (b) 2n (c) 4n (d) n.

50. Average binding energy of a nucleon inside a nucleus is about (a) 8 MeV (b) None of these (c) 8 Joules (d) 13.6 eV.

51. A mass m is suspended separately by two different springs of same length and spring constant k₁ and k₂ gives the time-period t₁ = 2 sec and t₂ = 3 sec respectively. If same mass m is connected by both springs in parallel, then time-period t of the combination is (a) (b) 5 sec (c) 1.2 sec (d) .

52. A double convex thin lens made of glass of refractive index 1.6 has radius of curvature 15 cm each. The focal length of this lens when immersed in a fluid of refractive index 1.63 is (a) 125 cm (b) + 407.5 cm (c) 25 cm (d) - 407.5 cm.

53. The amplitude of a wave disturbance propagating along positive X-axis is given by at t = 4 sec and at t = 4 sec where x and y are in metre. The shape of wave disturbance does not change with time. The velocity of the wave is (a) 0.5 m/s (b) 4 m/s (c) 2 m/s (d) 1 m/s.

54. Equivalent resistance between A and B is

(a) (b) (c) (d) R.

55. Two vectors of same magnitude have their resultant equal to difference of the magnitudes of two given vectors, then the angle between the vectors will be (a) 90° (b) 180° (c) 120° (d) 30°.

56. A horizontal rod PQ of mass M and length L is hinged at one end P. The rod is kept in horizontal position by a massless string tied to point Q. When the string is cut, the initial angular acceleration of the rod is (a) (g/L) (b) (2/3)(g/L) (c) 2(g/L) (d) (3/2)(g/L).

57. If K, s and T stand for thermal conductivity, electrical conductively and absolute temperature of a metal, then (a) K + s = T (b) (c) (d) K - s = T.

58. The number of turns in the primary and the secondary coils of a transformer are the secondary coils of a transformer are 1000 and 3000 respectively. If 80 volt ac is applied to the primary coil of a transformer, then the potential difference across the secondary coil will be (a) 0.08 volt (b) 0.24 volt (c) 2400 volt (d) 240 volt.

59. The magnetic field at a point at a large distance x at the axis of a current carrying circular coil of small radius is proportional to (a) 1/x³(b) x³ (c) 1/x² (d) x².

60. A particle P is moving is a circle of radius 'a' with a uniform speed v. C is the centre of the circle and AB is a diameter. The angular velocity of P about A and C are in the ratio (a) 1 : 1 (b) 1 : 2 (c) 2 : 1 (d) 4 : 1.

61. Salting out action of soap is based on (a) Solubility product (b) Complex ion formation (c) Acid-base neutralization (d) Common ion effect.

62. Predict the product (C) in the following reaction sequence :

(a) 2-Methylcyclopentene (b) 2-Methylcyclopentanol (c) 1-Methylcyclopentanol (d) Cyclohexene .

63. Schottky defect in crystals is observed when (a) An ion leaves its normal site and occupies an interstitial site (b) Density of the crystal is increased (c) Equal number of cations and anions are missing from the lattice (d) Unequal number of cations and anions are missing from the lattice.

64. The rate constant is given by the equation which factor should register a decrease for the reaction to proceed more rapidly (a) A (b) Z (c) E_a(d) T.

65. Rate constant of a first-order reaction is 0.0693 min^-1. If we start with 20 mol L^-1, it is reduced to 2.5 mol L^-1 in (a) 30 min (b) 10 min (c) 40 min (d) 20 min.

66. Hydrogen bond is strongest in (a) all are equally strong (b) F?H---N (c) F?H ---O (d) F?H---F.

67. SO₂ can act as better reducing agent in (a) none of the other three choices given here (b) neutral medium (c) acidic medium (d) basic medium.

68. Alkyl halides can be obtained by all methods except (a) CH₃¾CH₂ ¾ CH₃ + Cl₂ (b) CH₃CH₂OH+HCl (c) CH₃COOAg + Br₂/CCl₄® (d) C₂H₅OH+NaCl®.

69. Which of the following has the smallest size ? (a) Cl^- (b) Na⁺ (c) F^- (d) Mg²⁺.

70. van der Waal's equation of state explains the behaviour of (a) easily liquifiable gases (b) ideal gases (c) real gases. (d) noble gases only.

71. Which does not act as Bronsted acid ? (a) HSO₃^- (b) CH₃ COO^- (c) NH₄⁺(d) HCO₃^-.

72. A number of ionic compounds, e.g., AgCl, CaF₂, BaSO₄ are insoluble in water. This is because (a) These molecules have exceptionally high attractive forces in the lattice. (b) Water is not a good ionizing solvent (c) Ionic compounds do not dissolve in water (d) water has a high dielectric constant.

73. Baking soda is (a) A Basic salt (b) Double salt (c) Acidic salt (d) Complex salt.

74. Number of amino acid units in insulin is : (a) 21 (b) 61 (c) 31 (d) 51.

75. Boyle's law may be expressed as (a) (dP/dV)_T = - K/V (b) (dP/dV)_T= K / V (c) (dP/dV)_T = - K / V² (d) none of the other three choices given here .

76. If 0.829 g of CaO (MW = 56) and 0.739 g of CO₂ (MW = 44) are combined according the equation CaO(s) + CO₂(g) ® CaCO₃ (s), then, the limiting reagent is (a) Ca CO₃ (b) CaO (c) none of the other three choices given here (d) CO₂.

77. Which ligand is capable of forming low spin as well as high spin complexes ? (a) CN^- (b) CO (c) NH₃(d) NO₂^-.

78. For the following cell with gas electrodes at p₁ and p₂ as shown cell reaction is spontaneous if (a) p₁ >p₂ (b) p₁ = 0 (c) p₁ = p₂ (d) p₁ < p₂.

79.  p-bonding is not involved in : (a) ferrocene (b) dibenzene chromium (c) grignard reagent (d) zeise's salt.

80. The molecularity of a reaction is (a) Always two (b) different than the order (c) same as its order (d) may be same or different as compared to order.

81. The melting points of most of the solid substances increase with an increase of pressure. However ice melts at a temperature lower than its usual melting point when the pressure is increased. This is because (a) Ice is less denser than water (b) The chemical bonds break under pressure (c) Pressure generates heat (d) Ice is not a true solid.

82. Silicones are formed by hydrolysis of ______ followed by subsequent polymerization. (a) aryl chlorosilanes (b) grignard reagent (c) both alkyl & aryl chlorosilanes (d) alkyl chlorosilanes.

83. Activation energy of a chemical reaction can be determined by (a) changing concentration of reactants (b) evaluating rate constants at two different temperatures (c) evaluating velocities of reaction at two different temperatures (d) evaluating rate constant at standard temperature.

84. Benzaldehyde reacts with ammonia to form (a) Urotropine (b) Ammonium chloride (c) Benzaldehyde ammonia (d) Hydrobenzamide.

85. The diagram given below represents a Daniell cell. When the zinc rod and the copper container are connected as part of a completed electrical circuit, a current flows in this circuit, which of the following statements about this system is NOT correct.

E°_Zn⁺²_/Zn= -0.76 V; E° _Cu⁺²_/Cu =+0.34 V (a) sulphate ion migrate through the porous pot from the zinc compartment to the copper compartment (b) electrons flow from the zinc to the copper through the external circuit (c) if both the solutions are molar, then the cell can produce a maximum e.m.f of 1.10 V (d) the zinc electrode gradually dissolves.

86. The hybrid state of N in NO₃^- is same as that of S in (a) H₂SO₄ (b) H₂S (c) SO₄^2- (d) SO₃.

87. At low temperature, the slow addition of bromine to CH₂=CH¾CH₂¾Cº CH, gives (a) BrCH₂¾CHBr¾CH₂¾CºCH (b) CH₂=CH¾CH₂¾CBr=CHBr (c) CH₂=CH¾CH₂¾CH₂¾CHBr₂ (d) CH₃¾ CBr₂ ¾CH₂¾ C º CH .

88. A certain quantity of iron wire was dissolved in dil. H₂SO₄. The solution required 98.5 ml of 0.1 N KMnO₄ solution for complete oxidation. The weight of iron wire is (a) 0.276 g (b) 0.75 g (c) 0.828 g (d) 0.552 g.

89. 3-methyl-2-pentene on reaction with HOCl gives (a) (b) (c)

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