Lubrication is the most common means of reducing friction, for example the motor oil used in car engines. While friction is increased by give the surfaces a rough or textured feel such as in sand paper, hiking boot soles, and tire treads. Of course conversely friction can also be decreased by smoothing surfaces out, the reason swimmers shave their bodies or use wet suits to increase their speed.
1
Answers
Lubrication is the most common means of reducing friction, for example the motor oil used in car engines. While friction is increased by give the surfaces a rough or textured feel such as in sand paper, hiking boot soles, and tire treads. Of course conversely friction can also be decreased by smoothing surfaces out, the reason swimmers shave their bodies or use wet suits to increase their speed.