A background check is required of all applicants for the above licenses or. certificates. The following is required prior to going to Greeley/Weld Criminal. Justice Records Section, 1551 N. 17th Avenue, Greeley, CO for the background. check.
Friction is a force that acts against a moving object to slow it down. A type of friction is air resistance. Friction opposes the direction in which the object is moving, causing the object to decrease in speed, or stop all together.
For example, a rough surface (such as a carpet) exerts more friction than a smooth one (such as an ice skating rink). The state of the material an object is in contact with also affects friction. There is more friction between two solid surfaces, for example, than between a solid object and a gas.