Cross-country Skiing The physics involved in cross-country skiing are very different from downhill skiing.  Friction is an important component.  Skiing across flat terrain requires a skier to push along under his own power, which can be assisted by the use of poles.  By pushing his skis on the snow in the direction perpendicular to the ski, the skier pushed off the snow surface.  A perpendicular force is exerted on the ski by the snow as the skier pushes off.  The force in the direction of motion pushes the skier forward.  The opposite leg is either raised or gliding on the snow.  With a forward motion, the skier pushes off with the opposite leg and repeats the actions.  Pushing off the snow with greater force will allow the skier to accelerate faster in the desired direction.  To slow down, the “snowplow” is used.  The skier forms a V-shape with the ski fronts, resulting in a force opposite the direction of motion, slowing and then stopping him.

Image courtesy of real-world-physics-problems.com

Home History of Skiing Introduction Downhill Skiing Cross-Country Skiing Ski Jumping Inertia Action-Reaction Bibliography