# AP 8th Physical Science Mock Test 2023 For Chapter – 2 : ” Friction ” Online Practice Test

1. Using of lubricants or ball bearings causes ............... in friction
2. True statement
3. Which is not true ?
4. Friction depends on which factors ?
5. Find the correct statement
6. 10 kg brick with dimensions 502520 cm placed horizontally on the floor . The static friction id 'f ' . What happened to static friction when it placed vertically n the floor ?
7. Friction produces .............
8. The material required to perform an activity to observe the effect of contact force on friction are
9. Identify friction force direction
10. In which of the following cases , drag doesn't exist
11. Friction depends on
12. Sprinkling powder on carrom board __________ is the friction
13. Identify true statement
14. The friction in the cycle is chain ................. by adding oil
15. On which of the above components that friction depends ?
16. Friction is independent of
17. To overcome friction ............ are used in machinery
18. Friction produces
19. The friction exerted by moving body is called
20. The friction acting on the body which is at rest is
21. The friction exerted by fluid is called
22. The friction which is least among all the frictions
23. The friction exerted by a rolling body is
24. The friction opposes the ................... between surfaces in contact
25. Friction depends on the ............. of surfaces
26. Friction produces
27. Sprinkling of powder on the carrom board .............friction
28. Sliding friction is ................ than the static friction
29. Friction is ............... of area of contact
30. Friction can be decreased by using
31. Friction is.............. to normal force
32. _____________ is called necessary evil
33. The maximum frictional force offered by a surface can be measured by using
34. As the normal force increases frictional force exerted by body is
35. The special shapes of birds reduce
36. ................. irregularities increases friction
37. To light a match stick we need ................ force
38. To light a match stick we need ................ force
39. Match the following
1. Static friction   ( ) a. Object in motion
2. Sliding friction ( ) b. Ball bearings
3. Rolling friction ( ) c. Object at rest
40. Match the following
1. Fluid friction   ( ) a. Decrease the friction
2. Friction            ( ) b. Nature of surface
3. Lubricants       ( ) c. Drag
41. Match the following
1. Normal force           ( ) a. Increase the friction
2. Area of contact        ( ) b. Friction is independent
3. Shape of birds         ( ) c. Produces heat
4. Friction                     ( ) d. To overcome fluid pressure
42. ......................... is the friction which comes into play when surface of one object moves relative to the other surface of another object
43. What purpose are served by bearings in machines ?
44. The force applied by the floor on the object moving is called
45. Which of the following is false statement about frictional force ?
46. ............................ is the friction which comes into play when surfaces of objects are at rest relative to each other
47. ............................ is the friction which comes into play when surfaces of one object moves relative to surface of another object
48. When one body rolls over the surface of the other body he friction offered is called
49. Write the order of friction
50. The substances which reduce friction are called
51. What are the factors which influence friction ?
52. The frictional force exerted by fluid is called
53. The frictional force of an object in a fluid depends on
54. If friction was absent can you light a match stick ?
55. Hard metal balls are used  between rolling parts in a machine . How does it reduces friction ?
56. A car moving on a concrete road entered on glacier . The driver applied brakes . Describe its motion
57. Why do we use grease between moving parts of motor vehicles ?
58. What is effect of roughness on frictions ?
59. Why do Gymnasts apply some coarse substances on their hands ?
60. What is the effect of area of contact on frictional force ?
61. Why do we need to change the tyres when its threading is worn out ?
62. Why shape of aeroplane is similar to birds ?
63. Required materials for understanding rolling friction are
64. What is the conclusion on the principal of ball bearings ?
65. In ball bearings activity the top lid can easily rotate because
66. Which force is responsible for stopping the rotation of water ?
67. Where do you think scientists get hint for the special shapes like aeroplanes ?
68. Why do we pour a few drops of oil on the hinges of a door ?
69. Which of the following move easily and fastly ?
70. Cars , trucks tyres are threaded . why ?
71. The devices which reduce friction between rotating shafts of machine tools is
72. Which of them are fluids ?
73. The frictional force exerted by fluids is called
74. Fluid friction is
75. Find the evil of friction
76. What are the advantages of friction ?
77. Explain why sportsman use shoes with spikes ?
78. What conditions are needed for static friction to come into play ?
79. Which of the following is practical application of static friction ?
80. Which of the following is example for showing the existence of sliding friction ?
81. We can measure frictional force by using ____________ in some situations
82. Ways of reducing friction
83. ........... are used in machinery
84. ........... are used in automobiles and aeroplanes
85. .................... decreasing irregularities of surface
86. Does friction act on a table resting on the floor ?
87. Can we reduce friction to zero?
88. What are th forces acting on book in horizontal direction ?
89. Push a heavy box which is kept on a floor and it does not move first , after increasing the applied force it moves . Can you guess the reason why it does not move first ?
90. Push a heavy box which is kept on a floor and it does not move first , after increasing the applied force it moves . Can you guess when does the box tends to move?
91. Find the false statement ?
92. Find the false one
93. Find the true statement
94. Find true statement
95. It is used for

96. A : Gymnast apply some coarse substance for a better grip
B : The substance which increase friction is called lubricants
97. A : Ball bearings used in machinery
B : Automobiles and aeroplanes are steam lined to reduce friction
98. A : There is no need of friction in transport
B : We can reduce the friction to zero
99. A : Static friction < Sliding friction < Rolling friction
B : If friction is absent we can light match stick
100. It represents the