# AP 9th Physical Science Mock Test 2021 For Chapter-7:”Gravitation” Online Practice Test

1. The expression for centripetal acceleration
2. ................ found the acceleration due to gravity value on the earth is 981 cm/s2
3. The value of universal gravitational constant was found by
4. The time period of satellite to complete one revolution around the earth is.........
5. The value of 'g' on the earth..................... m/s2
6. The formula to find acceleration due to gravity is
7. The weight of body , whose mass is 10 kg is...................
8. The value of 'g' on the moon is that on earth . A body weighing 60 kg on the earth , has weight on the moon is.............
9. The body is projected vertically up . The distance covered inits last 2 seconds upward motion is...................m
10. The S.I unit of G
11. The moon takes ............ days to complete one revolution around the earth
12. In vacuum all the freely falling objects have same
13. The weight of a body is measured by an instrument called
14. Radius of earth is nearly ........ km
15. The mass of earth is nearly............kg
16. The value of 'G' is
17. According to Kepler's law Time period (T) and Radius(R) of the planets are related as
18. The force of attraction of a body due to earth is called
19. Formula for centripetal force F =
20. The force of gravitational between two objects m1 , m2 separated by a distance 'R' is related as follows
21. The weight of a child on the surface of earth is 48 N . His weight at the centre of the earth is
22. The weight of a man on the surface of earth is 96 N. His weight of moon is
23. Assertion : 10 kg body weight 98 N
Reason  : Weight W = mg
24. As we move from equator to poles the value of 'g'
25. The simple method to locate the centre of gravity of an object is
26. When a body falls freely it experiences
27. The centre of gravy of a triangular lamina lies at its
28. When a stone and a leaf were dropped from same height in your class room then the observation is
29. Match the following
1. Mass of the earth                               ( ) a.1.67 m/s2
2. Radius of the earth                            ( ) b. 3.85 km
3. Distance between moon and earth ( ) c. 6 kg
4. Value of 'g' on moon                          ( ) d. 6.4 m
30. Choose the correct match
1. Centripetal force                     ( ) a. gm/R2
2. Gravitational force                 ( ) b. mv2/R
3. Weight                                      ( ) c. GMm/R2
4. Acceleration due to gravity  ( ) d. mg
31. In uniform circular motion , which of the following are correct
32. A body is projected vertically up . The distance covered by it in last second of upward motion
33. A stone is thrown vertically up from the tower of height 25, with speed of 20 m/s then the time it takes to reach the ground
34. The weight of 1 kg mass of body
35. Two spherical balls of mass 20 kg each one placed with their centres 20 cm apart . Find the gravitational force of attraction between them
36. What is the force that acts on planets move around the sun ?
37. Calculate the tension in a string that whirls a 2 kg-toy in a horizontal circle of radius 2.5 m when it moves at 3m/s
38. Motion of body with constant speed in circular path is called
39. Newtons explained the concept of moon by using
40. Moving body with constant speed 'v' in circular path radius R then the direction of velocity vector changes its direction and appear as
41. The sum of the magnitudes of the changes in velocity during a complete revolution will be equal to
42. The acceleration that changes only the direction of velocity of a body is called
43. In uniform circular motion a net force acts ..................... the centre
44. The net force which change only the direction of velocity of body is called
45. Distance of moon from centre of the earth is
46. The force of gravity decreases with................. in distance of object from centre of earth
47. The motion of a body under the influence of force of gravity alone is called
48. The experience of freely falling body is called
49. The state of being stable is called
50. The following explains
51. Fc = , here Fc is
52. The mass of the earth (M) =
53. Radius of earth is (R) =
54. Fulfill the following formula
=
55. Ink is mixture of a dye in water . we can separate the components in the ink using evaporation , the correct observation in the experiments is
(i)Water is separated in the form of vapour
(ii)Dye component doesn't evaporate
(iii)Water and dye components gets evaporated
(iv)Dye components gets sublimated
56. During free fall condition , the body is i state of
57. The centre of gravity is the point where _________ of the body acts
58. The body is in equilibrium when the weight vector goes through the ______ of the body
59. Uniform circular motion is the motion of body with constant speed in
60. Newton explained the motion of moon by using the concept of motion
61. In uniform circular motion A net force acts towards
62. In uniform circular motion a net force acts towards the centre . This net force is called
63. The net force which change only the direction of the velocity of a body is called
64. F = ma
The above formula describes
65. Centre of gravity is simply defined as
66. The point where total weight appears to act is called
67. Here the many small arrows represent
68. Weight of an object is depending on
69. During free fall condition , the body is in the state of
70. The body is in equilibrium when the
71. 2 kg body weighs is equal to
72. A : F = ma
B : W = mg
73. Find the time taken by the body projected vertically up with a speed of u , to return back to the ground
74. A stone is thrown vertically up from the tower of height 25m with a speed of 20 m/s. What time does it take to reach the ground ?
75. A body is projected vertically up . what the distance covered in its last second of upward motion ? ( g = 10 m/s2)
76. Two bodies fall freely from different heights and reach the ground simultaneously  . The time of descent for the first body is t1 = 2s and for the second t2 = 1s.At what height was the first body situated when the other began to fall ? ( g= m/s2 )
77. Name the following
78. The following activity shows
79. Balancing ladder is depend on
80. Which of the following shows the body falls freely then it experience weightlessness ?
81. In following figure what happens in b ?
82. In the following figure , we see that moon falls around earth rather than straight into it . If the magnitude of velocity were zero , how would it move ?
83. Symbol for Gravitational Constant is
84. Formula for Acceleration due to gravity
85. S.I units for Gravitational constant
86. Value for acceleration due gravity
87. Match the correct values
1. Mass of the earth            ( ) a. 6.4 km
2. Gravitational constant  ( ) b. 6 kg
3. Radius of earth               ( ) c. 9.8 m/s2
88. Match the following with their symbols
1. Centripetal acceleration       ( ) x. g
2.  Acceleration due to gravity ( ) y. Fc
3.  Centripetal force                    ( ) z. ac
89. No matter how we throw the objects , the direction of acceleration is always is
90. ................. force acts on planets move around the sun
91. Which of the following are examples for centre of gravity ?
92. During free fall of our body from the height we feel
93. Statement 1 : Acceleration due to gravity is independent of mass of the body
Statement 2 : Symbol for acceleration due to gravity is G
94. When we throw the stone vertically up then 'g' is
95. When we drop book and paper separately then we conclude that
96. In uniform circular motion activity , the speed of block is
97. In the activity of uniform circular motion , Which of the following is not a required material ?
98. Which of the following are not related to gravitation ?
99. Newton is SI unit for
100. SI unit for centripetal force is