Friction

Our topic is on friction and what it is. So what is friction? Friction is the “evil” of all motion. No matter which direction an object moves in, friction will pull it the other way. Move something right, friction pulls it left. Move something up, friction pulls it down.
Friction depends partly on the smoothness of the contacting surfaces, a greater force being needed to move two surfaces past one another if they are rough than if they are smooth. Although two objects might look smooth, microscopically, they’re very rough and jagged. However, friction decreases with smoothness only to a certain degree. Friction actually increases between two extremely smooth surfaces because of increased attractive electrostatic forces between their atoms. Friction does not depend on the amount of surface area that are in contact between the moving bodies or on the relative speed of the bodies. What it does depend on though, is the magnitude of the forces holding the two bodies tog...