When a soccer ball
moves along a surface, there is a component of force that is parallel to the surface.
This parallel force is called the frictional force (Cutnell
& Johnson). Frictional forces are always tangent to the surfaces. A soccer
ball rolling across a field creates friction, the friction being opposite the
direction the ball is traveling.

Physics uses the equation _{} for objects that slide
against one another. In the equation the frictional force (f) is equal to the
normal force (_{}) multiplied by the coefficient of friction (_{}). The coefficient of friction will vary with the ball and
the type of surface with which it interacts. The more friction there is between
the ball and the field, the slower the ball will move across the field.

Therefore, the coefficient of friction will tell us how
fast or slow a ball will travel. It only makes sense that the higher the
coefficient of friction is, the slower the ball will travel
(Oceansiderevolution.com).

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An example found at
Oceansiderevolution.com:

What happens if you kick a soccer ball
without giving it any spin? – Your foot will give the ball an initial speed (_{}) and an initial angular speed of 0. The interaction of the
ball and the grass will cause friction. The ball will initially slide across
the field, start to rotate, and eventually start rolling without slipping. This
will happen as its center-of-mass speed equals its angular speed (around its
center of mass).

Suppose you want to kick the ball so
that it immediately starts rolling without slipping. How could you do this? You
would give the ball “topspin” by striking the ball a distance (s) above an
imaginary horizontal line that passes through the ball’s center. Where should
you kick the ball in order to do this? The answer works out to be s=0.4R. You
would have to kick the ball a little less than half the radius of the ball
above its center line (as shown in the picture above).

Information for this page was obtained from:

http://www.oceansiderevolution.com/EINSTEIN_4.htm

Cutnell & Johnson Physics. Volume 1. 6^{th} Edition.