What do you mean by static and dynamic friction ? Discuss in brief

What do you mean by static and dynamic friction ? Discuss in brief.

There are two types of frictions :

  1. Static friction : The opposing force that comes into play when one body tends to move over the surface of another, but the actual motion has not yet started, is called static friction.
  2. Dynamic friction : Dynamic friction is the opposing force that comes into play when one body is actually moving over the surface of another body. Further, dynamic friction may be of two types i.e., sliding friction and rolling friction. These are described below :
    (i) Sliding friction : The opposing force which comes into play when one body is actually sliding over the surface of the other body is called sliding friction. For example, ice-skating and in planting the pole in pole vault.
    (ii) Rolling friction : The opposing force which comes into play when, one body is actually rolling over the surface of the other body is called rolling friction. For example, when a hockey or cricket ball is hit, it rolls on the surface of the ground. It stops after some time due to rolling friction. Such- type of friction is widely seen in games and sports.