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2. KEY PROPERTIES
The key properties of a court surface are as follows:
Friction: The resistance to relative movement between a court surface and an object in
contact with that surface. The coefficient of friction (COF) is the ratio of the
horizontal and the vertical components of force between the ball and the surface. A
rougher surface has a greater COF, causing a greater reduction in the horizontal
velocity and the surface to play 'slower'.
Energy restitution: The energy returned by the surface (and ball) following impact. A
decrease in energy return is manifested as a reduction in vertical velocity of the ball
after impact. The coefficient of restitution (COR) is the ratio of the vertical velocity of
the ball after the bounce to that before impact. A surface that yields a higher COR is
typically perceived to play slower, because the player has more time to reach the ball.
Topography and dimensions: The geometric regularity of the surface (evenness); the
gradient (slope) and planarity designed to assist drainage; and the relative locations of
court markings (dimensions).
Consistency: The uniformity of surface properties over the entire playing area and
their stability with time, use and maintenance.
