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8th Class Science Friction Question Bank Friction Conceptive Objective Problems

  • question_answer
    Four similar boxes are labelled I, II, III, and IV. The masses of I and III are equal and the masses of II and IV are equal. The mass of box I is smaller than that of box II. Boxes I and II are placed in a grass field and boxes III and IV are placed on a marble floor. Which box requires the maximum force to be moved?

    A)  I                                             

    B)  II

    C)  III                                          

    D)  IV

    Correct Answer: B

    Solution :

      Irregularities on surfaces offer resistance to the motion of an object over it. This resistance is called friction. The more the irregularities on the surface, the more is the friction. Hence, more force is required to move an object placed on an irregular surface. Since irregularities present on a grass field are more than those present on a marble floor, more force is required to move a box placed in the grass field. Boxes I and II are placed in a grass field. Therefore, boxes I and II require more forces to be moved than those required by boxes III and IV. The opposing force of friction does not remain the same for heavier and lighter objects. Frictional force is greater for heavier objects and smaller for lighter objects. Since box II is heavier than box I, box II requires the maximum force to be moved. The correct answer is B.


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