51. On a stationary sail boat, air is blown from a fan attached to the boat. The boat
52. Rainbow is due to
53. Stars which appear single to the naked eye but are double when seen through a telescope are
54. ML2T-2 is the dimensional formula for
55. Solar eclipse will take place when
56. Isotopes of an element contain
57. One watt-hour is equivalent to
58. Sir C.V. Raman was awarded Nobel Prize for his work connected with which of the following phenomenon of radiation?
59. In which of the following industries is mica as a raw material?
60. Radiocarbon dating technique is used to estimate the age of
61. Identify the vector quantity from the following
62. Large astronomical telescopes always use as objective
63. One should not connect a number of electrical appliances to the same power socket because
64. Rainbow is produced when sunlight fall on drops of rain. Which of the following physical phenomena are responsible for this? DiffusionRefractionInternal reflection
65. Natural radioactivity was discovered by
66. Planets are
67. One nanometer is equal to
68. Mica is used in electrical appliances such as electric iron because mica is
69. It is easier to roll a barrel full of coal tar than to pull it because
70. Minimum number of unequal vectors which can give zero resultant are
71. Intensity of sound has
72. Rain is falling vertically downwards. To a man running east-wards, the rain will appear to be coming from
73. An aeroplane is flying horizontally with a velocity of 600 km/h and at a height of 1960 m. When it is vertically at a point A on the ground a bomb is released from it. The bomb strikes the ground at point B. The distance AB is
74. Radiocarbon is produced in the atmosphere as a result of
75. It is easier to roll a stone up a sloping road than to lift it vertical upwards because