For rubber on tarmac close to 1 0.
Rubber wood coefficient of friction.
Hard rubber on dry wood.
Static and kinetic coefficient of friction.
Soft plastic on dry wood.
The coefficient of friction is the ratio of a force to a force and hence has no units.
The coefficient of static friction typically denoted as μ s is usually higher than the coefficient of kinetic friction.
Typical values for the coefficient of friction when sliding is occurring i e.
The friction force of a 100 lbwooden crate pushed across a concrete floor with friction coefficient of 0 62 can be calculated as.
Where μ s is the coefficient of static friction and μ k is the coefficient of kinetic friction.
Hard plastic on dry concrete.
Soft rubber on dry wood.
The dynamic coefficient of friction are.
For example ice on steel has a low coefficient of friction while rubber on pavement has a high coefficient of friction.
The coefficient of friction depends on the materials used.
Soft plastic on dry concrete.
Coefficients of friction between materials are best determined through testing.
The friction force is the force exerted by a surface when an object moves across it or makes an effort to move across it.
The static and kinetic friction coefficient values reference table shown in this article will be helpful for finding the cof values of commonly used materials.
Hard rubber on dry concrete.
F f frictional force n lb.
For polished oiled metal surfaces less than 0 1.
F f μ n 1.
N normal force between the surfaces n lb there are at least two types of friction forces.
Showing the concept of coefficient of friction.
Ff 0 62 100 lb 62 lb 1 lb 0 4536 kg example car stopping distance.
Coefficients of friction range from near zero to greater than one.
Static friction results from the normal force of two objects in contact acting opposite the intended motion of one surface against the other.
However it is possible to find tables in the literature for friction coefficients between various materials.
μ static μ s or kinetic μ k frictional coefficient.
Soft rubber on dry concrete.
Now slowly increase the angle of the ramp until the rubber just begins to slip.
For example static friction can prevent an object from sliding down a sloped surface.
A good way to determine the coefficient of friction is to do a test with the actual materials.
Static friction is friction between two or more solid objects that are not moving relative to each other.
The maximum force of static friction can be calculated by multiplying the normal force by the coefficient of friction specific to the pair of materials in contact.
The frictional force can be expressed as.
In your case build a ramp made of wood and place a sample of the rubber material on the ramp.