Changes

: When a '''lubricant''' is added to the boundary between two surfaces the [[friction]] is decreased.

: [[Lubricating Oil]] is a fraction of [[Crude Oil]] often used as [[lubrication]] in machines such as [[car]]s.

: When two surfaces rub together the [[friction]] causes [[energy]] to be [[Energy Transfer|transferred]] to the [[Thermal Energy Store|thermal energy store]] of the [[object]]s. [[Lubrication]] of the surfaces reduces the unwanted [[Energy Transfer|energy transfer]] reducing the [[heating]] effect caused when two surfaces rub together.

: Drills often use [[water]] or [[Lubricating Oil|oil]] to '''lubricate''' the surface which helps prevent the drill from getting too hot and [[melting]].