Explain various types of friction suggest a few methods to reduce friction

Explanation

Various types of friction:-
`(i)` Static Friction :
Static friction is the force which opposes the initiation of motion of an object on the surface.
The static friction does not depend upon the area of contact. It is denoted by `vecf`.
`(ii)` Kinetic Friction :
If the external force acting on the object is greater than maximum static friction, the objects begin to slide. When an object slides, the surface exerts a frictional force called kinetic friction `f_(k)` (also called sliding friction or dynamic friction).
`(iii)` Rolling Friction :
The force of friction that comes into act when a wheel rolls over a surface.
Methods of reduce friction :-
`(i)` By polishing the surface
`(ii)` By lubricating
`(iii)` By using ball bearings.