Physics

Skiing is a sport that is very dependent upon the laws of physics.

[http://home.mesastate.edu/~jerry/gmnc/waxing.htm]

Waxing the ski base; waxing increases the static friction, allowing more thrust to a kick.

Static Friction:

Where: is the coefficient of friction of the grip wax

P is the Pressure between small point on ski and snow in center of ski

g is the length of the grip-wax zone

a is the inner boundary of snow-ski contact zone.

b is the outer boundary of snow-ski contact zone

This is providing that the downward force (F) is smaller than the force needed to close the ski (C). [That is: F > C * (1 - g/b)]  To close the ski means the force needed to make the natural upward bend in a ski flat against a surface. This means that there is still some bend left in the ski and the contact with the snow is not over the entire kick zone.

This equation can be solved to get S = * F (g^2 - a^2) / (b^2-a^2) for F<C

Free Body Diagram:

When going down a hill the free body diagram looks like this:

[http://www.hesston.edu/academic/faculty/nelsonk/PhysicsResearch/Ski/paper.htm]

where Ff = mg

Fg = mg