Glossary
In physics, friction refers to a force that strives to counteract the relative motion between two surfaces that are in contact with each other. Friction arises through unevenness and adhesion between the surfaces.
An example of friction in traffic is that brake calipers create friction with the tire which ensures that the speed is reduced, or that the tires at a lower speed slow down your car, due to friction with the road conditions. This friction between the tires and the road is the way the car moves forward in the first place.
