Give 2 eg to reduce friction

There are more than two ways of reducing friction: a.by polishing the surface(the another the surface the lesser is the friction) b.by oiling the surface(by oiling the surface the surface becomes smoother and also prevents the direct contact between the two surfaces by filling up the dents and forming a film over the surface) c.using ball bearings or roller bearings(if we use ball bearings then the sliding friction is converted to rolling friction and since rolling friction is less than sliding friction the frictiokn reduces) *rolling friction is less then sliding friction because the point of contact between the two surfaces is less and thus the interlocking between them also decrea see resulting in the decrease in the frictional force

*by polishing the surface *By adding wheels to the object *Streamlined body structure