coefficiant
Friction refers to the resistance that one surface or object encounters when moving over another. The two common forms of friction between two sliding surfaces are static friction and rolling friction.
Coefficient~Apex:)
cofficent .ilyy ; (KP)
The friction is a number that represents the resistance to sliding between two surfaces in contact with one another. It is measured in Newtons (N).
Unitless, surfaces
Yes but make sure you are clear in your understanding between the coefficient of friction and the force of friction. The force of friction is the force that resists the motion of two surfaces moving against one another. The amount of friction is determined by the product of the coefficient of friction and the normal (perpendicular) force that is pressing the two surfaces together. The coefficient of friction is a unit-less constant, that indicates how two surfaces compare to two other surfaces that are being pressed together the same amount. If the normal force is the same on two pairs of surfaces the pair of surfaces with the lowest coefficient of friction will experience the lower force of friction.
Surfaces which are rough create the most friction. Like cement, or sand paper.
Rolling friction is the force of friction between two surfaces when one surface rolls over another.Sliding friction is the force of friction between two surfaces when one surface is moving on another.
If the two surfaces are moving relative to each other, then the friction between them is Kinetic Friction. Prior to the surfaces moving there was Static Friction between them.
air resistance
Friction is caused when two surfaces come into contact with one another. The irregularities on the surfaces rub against one another and friction results. Friction opposes motion. That is to say, friction acts in the direction opposite to motion.
The force that acts whenever two surfaces or objects mass put past one another is friction