Science Part 1 Question Bank Solution – Q.1 (B) VII. Right or wrong sentence.

1. If the distance between two masses is doubled, the gravitational force between them becomes less than the previous force.
Ans: Right

2. The CGS unit of G is dyne.cm2/g2.
Ans: Right

3. The value of gravitational acceleration at the centre of earth is zero.
Ans: Right

4. The value of g is highest at the equator.
Ans: Wrong

5. The value of G varies from place to place.
Ans: Wrong

6. As we go above the earth’s surface, value of g increases.
Ans: Wrong

7. Free fall of an object does not depend on the mass of the object.
Ans: Right

8. Mass is a qualitative measure of the inertia of an object.
Ans: Wrong

9. The similarity between the properties of the first and eighth elements is called the octave rule.
Ans: Right

10. In Dobreiner’s triads, three elements appear to be arranged in ascending order of their atomic number.
Ans: Wrong

11. While designing the periodic table, Mendeleev considered the chemical and physical properties of the elements.
Ans: Right

12. The modern periodic table has 1 to 7 periods.
Ans: Right

13. The modern periodic table shows the molecular masses of the elements in each frame.
Ans: Wrong

14. p-block is composed of groups 1 and 2.
Ans: Wrong

15. To the left of the zig-zag line in the periodic table are the metal elements.
Ans: Right

16. The valency of the elements in group 2 is 1.
Ans: Wrong

17. Nanometer unit is used to measure atomic radius.
Ans: Wrong

18. Moving from left to right, the size of the atom decreases.
Ans: Right

19. All the elements in the halogen family are gases.
Ans: Wrong

20. The elements lithium and beryllium are in the same period because their valencies are similar.
Ans: Wrong

21. Beryllium and calcium are alkaline earth metals.
Ans: Right

22. The K and L shells of the elements Na and Mg contain electrons.
Ans: Right

23. The number of shells decreases in a group from top to bottom.
Ans: Wrong

24. The metallic character of the element decreases moving across a period from left to the right.
Ans: Right

25. The size of an atom depends on the number of valence electrons.
Ans: Wrong

26. Silicon is a metallic element.
Ans: Wrong

27. On moving down the group metallic character increases.
Ans: Right

28. Electronegativity is the metallic property of an element.
Ans: Wrong

29. If edible oil is left aside for a long time, it will get rancid.
Ans: Right

30. The alternating current is an oscillatory current.
Ans: Right

31. Live wire and neutral wires have a 220 V potential difference.
Ans: Right

32. Increasing the current passing through the wire decreases the magnetic field intensity.
Ans: Wrong

33. Galvanometers are used for electrical measurements.
Ans: Right

34. The frequency of the alternating current is 50 Hz.
Ans: Right

35. Electric motors are devices that convert electrical energy into mechanical energy.
Ans: Right

36. The dew point temperature does not depend on the amount of vapor in the air.
Ans: Wrong

37. The specific heat capacity of water is 1 cal / g °C.
Ans: Right

38. The latent heat of vaporisation is a term referred for the conversion of gas into liquid.
Ans: Wrong

39. Calorimeters are used to study anomalous behaviour of water.
Ans: Wrong

40. During reheating, ice is converted to water at a temperature of 0 °C.
Ans: Right

41. 1 kg of dry air at a temperature of 40 °C can hold a maximum of 49 g of water vapour.
Ans: Right

42. Calorimeters are used to measure specific heat capacity.
Ans: Right

43. All metals have the same specific heat capacity.
Ans: Wrong

44. Humidity relative to dew point temperature is 100%.
Ans: Right

45. The unit of absolute humidity is kg /m3
Ans: Right

46. 1 calorie is 4.81 joules.
Ans: Wrong

47. The incident rays and refracting rays are on opposite sides of the normal.
Ans: Right

48. Purple has the lowest refractive index.
Ans: Wrong

49. The speed of light varies in different media.
Ans: Right

50. Convex magnifying glass is called divergent magnifying glass and concave magnifying glass is called converging magnifying glass.
Ans: Wrong

51. The image of the object in the human eye is formed on the cross screen.
Ans: Wrong

52. Hypermetropia can be corrected using concave lens of proper focal length.
Ans: Wrong

53. When the incident ray is parallel to the principal axis, the refracted ray passes through the principal focus.
Ans: Right

54. The image of an object at an infinite distance is obtained in a real and erect form through a convex magnifying glass.
Ans: Wrong

55. The power of the magnifying glass depends on the distance of the magnifying glass from object.
Ans: Wrong

56. The lens of the eye is flattened when looking at nearby objects.
Ans: Wrong

57. For a healthy human eye, the distant point is infinite distance.
Ans: Right

58. Vision defect that increases distance between the lens of the eye and retina of the eye is termed as myopia.

Ans: Right

59. The virtual image of object seen by the eye depends on the angle subtended by the object with the eye.
Ans: Right

60. Electrolysis is used to obtain pure metal from impure metal.
Ans: Right

61. Ionic compounds are soluble in kerosene.
Ans: Wrong

62. In solid state, ionic compounds conduct electricity.
Ans: Wrong

63. Mercury, silver, gold are highly reactive metals.
Ans: Wrong

64. In the electrolytic method, a layer of highly active metal is applied to a less active metal.
Ans: Wrong

65. In the electrolytic reduction of alumina, the lining of graphite acts as an anode.
Ans: Wrong

66. The electrolysis of alumina involves the use of fluorspar and cryolite to increase the melting point.
Ans: Wrong

67. Cassiterite is a copper ore.
Ans: Wrong

68. Diamond is a hard substance.
Ans: Right

69. Gold and silver are active metals.
Ans: Wrong

70. Halogen reacts with acid.
Ans: Right

71. Bauxite reacts with sodium hydroxide in the Bayer’s process.
Ans: Right

72. The number of electrons in the valence shell of a carbon atom is 4.
Ans: Right

73. Your body is made up of carbon.
Ans: Right

74. Carbon compounds contain only open chains of carbon atoms.
Ans: Wrong

75. Two carbon atoms can always form one or two covalent bonds.
Ans: Wrong

76. In general, saturated compounds are more reactive than unsaturated compounds.
Ans: Wrong

77. Benzene is a cyclic unsaturated hydrocarbon.
Ans: Right

78. Cyclohexane is a branched chain type of hydrocarbon.
Ans: Wrong

79. As one ascends in any homologous series, physical properties change gradually.
Ans: Right

80. There are different general molecular formula for all members of the homologous series.
Ans: Wrong

81. In LPG, butane is a flammable component.
Ans: Right

82. Substances that can give oxygen to other substances are called reductant.
Ans: Wrong

83. Potassium permanganate is an oxidizing compound in regular use.
Ans: Right

84. Colorless ethanol is in liquid state at room temperature.
Ans: Right

85. Ethanol is soluble in water in all proportions.
Ans: Right

86. Ester is a sweet-smelling compound.
Ans: Right

87. The escape velocity on the moon is less than the escape velocity on earth.
Ans: Right

88. India is the first country to discover the existence of water on the moon.
Ans: Right

89. The function of a satellite launcher is based on Newton’s second law of motion.
Ans: Wrong