Question

why a lubricant reduces friction

Answer 1

A lubricant is a substance introduced to reduce friction between surface in mutual contact, which ultimately reduces the heat generated when the surface moves.

Answer 2

Lubricants reduce friction as they eliminate the contact resistance between two solid surfaces or objects. when two solids surfaces come in contact, such as a sled being dragged across a floor, friction is the force that develops. this friction resists the relative motion between the two surfaces that develops. this friction resists the relative motion between the two surfaces that are in contact

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