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FRICTION - A NECESSARY EVIL

    


     Friction is an important phenomenon in our day-today life.  When you ignite a match stick, friction comes into play.


      When there is a relative motion between two bodies, friction arises.  That is, when one body moves over the other, frictional 
force develops.  Because of adhesive force between the contacting  surfaces, friction develops.  Friction is proportional to the weight of the body that is moving and it is an opposing force.  It always acts opposite to the motion of the body.  That is , if you pull a,heavy table right side, friction will oppose the motion and act towards left side.  If you push the table left side, friction will shift towards right side.

      Assume , a heavy iron safe is sitting on a rough floor.  The object weight acts on the floor, and the floor gives equal reaction on the iron safe.  Hence both the forces cancel each other.  Then, why cannot we move the safe easily.  It is only due to the opposing friction.


     Rolling friction is always less than the sliding friction.  So, small wheels are always attached to the mobile chairs, tables, boxes, beds etc.  The heavy and very long train moves swiftly on the iron track because the friction is greatly reduced (1. rolling friction  2. smoothness of iron wheels and the track).  Even if a child pushes a loose carriage standing on the rail track, it will roll to a long distance.

     Is there only negative attributes for friction? No.
  
     We are able to walk on the road and on the floor with out slipping only due to friction.

   We are able to control the vehicles because of road friction.  The brake system works mainly because of the friction process.  If there is no friction in the 'U' bend of the road, we cannot negotiate the curve on a two-wheeler and we will only skid off and fall down.

      For all machines (fan, engine) to work smoothly without using much energy, the friction should be greatly reduced.  That is why, ball-bearing and lubricant oil industries thrive.

      Recently, a new ink has been made.  It can be erased by rubbing (friction).  So be careful when some one signs a document even with a ink pen.

      So let there be friction and No friction.

Comments

  1. Jacky31 January 2021 at 00:15

    This comment has been removed by the author.

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  2. Jacky31 January 2021 at 00:19

    Thanks! Check out this cool comic on "Friction as a necessaary evil" https://dewwool.com/friction-is-a-necessary-evil-explain/

    ReplyDelete

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