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Example why: (i) we slip when step on ...

Example why:
(i) we slip when step on a banana pell.
(ii) lubricants are used in matchines.
(iii) a hover-creft travels much faster then a steamer pushing through water.
(iv) aeroplanes, missiles, and space ships have their front pointed.

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(i)The banana peel breaks the interlocking between our feet and ground.
(ii)The lubricant fills the fine pores or depressions in the surfaces.
(iii)Friction offered by water is more.
(iv) At the pointed ends the surface area is less.
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CENGAGE PHYSICS-FRICTION-MANDATORY EXERCISE. (EXERCISE SET I)
  1. Arrange the following in ascending order of their magnitude. Rolling...

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  2. Why do tyres of vehicles have tread?

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  3. Example why: (i) we slip when step on a banana pell. (ii) lubrican...

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  4. Two identical wooden blocks (A and B) are kept as known in the figure....

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  5. If a constant retarding force is applied on an object moving backwards...

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  6. You can keep a book pressed against a wall and prevent it from falling...

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  7. Why is it easier to maintain the motion than to state it?

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  8. In order to stop a car in shortest disatance on a horizontal road one ...

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  9. If the normal force is doubled, the coefficient of friction is

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  10. For a block kept on a table, the maximum force of static friction is F...

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  11. A scooter generally slips on an oily road, because

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  12. A body of mass 100 g is made just to slide on a rough surface by apply...

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  13. A weight 'W' rests on a horizontal plane. What will be the least force...

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  14. A horizontal force of 10 N is necessary to just hold a block stationar...

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  15. A mass of 4 kg rests on a horizontal plane. When the plane is graduall...

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  16. The ratio of mu(k) (kinetic friction) and mu(s) (state friction) is

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  17. What is the relation between the normal reaction acting on a surface a...

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  18. A block of mass 0.1 kg is held against a wall by applying a horizontal...

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  19. The block of mass m is in contact with a moving cart as shown in the f...

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  20. A block is placed on an inclined plane. The angle of inclination of th...

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