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SAI INTERNATIONAL SCHOOL
                                                          Class8
                                                  Home Assignment
                                                   Subject-Physics
                                                       CH-Friction
                                                Subtopic-Introduction


                       DIRECTION: Each of these questions contains an Assertion followed by Reason. Read them
                       carefully and answer the question on the basis of following options. You have to select the one
                       that best describes the two statements.
                       (a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
                       (b) If both Assertion and Reason are correct, but Reason is not the correct explanation of
                       Assertion.
                       (c) If Assertion is correct but Reason is incorrect.
                       (d) If Assertion is incorrect but Reason is correct.
                       (e) If Assertion & Reason both are incorrect.

               Assertion and Reasoning
                   1.   Assertion: It is difficult to walk on a smooth or slippery surface                     1
                       Reason: Friction between feet/shoes and the surface is less.
                   2.   Assertion: Rough surface offer more friction than smooth surface.                      1
                       Reason: Both surfaces have similar irregularities.
               MCQ
                   3.   Ram rolls four marbles having same weight on Icy, dry, sandy, and cemented             1
                       surfaces. On which surface will the stone go to maximum distance before it
                       stops?
                          (a) Icy
                          (b) Dry
                          (c) Sandy
                          (d) Cemented
                   4.   A boy is pushing a box from right to left. In which direction will friction act?       1
                          (a) Right to left
                          (b) Left to right
                          (c) Upwards
                          (d) downwards
                   5.   Two blocks of Iron of 1kg and 5 Kg are kept on a cemented floor which one of           1
                       them would require a larger force to move it from the rest position?
                          (a) No force required to move
                          (b) 1 kg
                          (c) 5 kg
                          (d) Same force for 1kg and 5kg
               True or False
                   6.   Friction experienced by an object depends on the weight of the object                  1
                   7.   If the area of contact increases friction increases.                                   1
                   8.   Direction of friction is opposite to the applied force.                                1
               Subjective Questions
                   9.   Suppose your writing desk is tilted a little. A book kept on it starts sliding down.   1
                       Show the direction of frictional force acting on it.

                   10.  Arrange the frictional force offered by following surfaces in increasing order:        2
                       newspaper, towel, dry marble floor, wet marble floor.

                   11.  Iqbal has to push a lighter box and Seema has to push a similar heavier box on         2
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