Wheels Reduce Friction
You must have seen attaches and other pieces of luggage fitted with rollers. Even a child can pull such pieces of luggage . Why is it so? Let us find out.When one body rolls over the surface
of another body, the resistance to its motion is called the rolling friction. Rolling reduces friction. It is always easier to roll than to slide a body over another. That is the reason it is
convenient to pull the luggages fitted with rollers. Can you now understand why wheel is said to be one of the greatest inventions of mankind? Since the rolling friction is smaller than the sliding friction, sliding is replaced in most machines by rolling by the use of ball bearings. Common examples are the use of ball bearings between hubs and the axles of ceiling fans and bicycles .
Notes
Friction - Notes
