Question

(4pts) olympic cross-country ski champion, henrik henrikson, is using a new ski wax, gripola, that is supposed to stop his ski from slipping backwards when he pushes off against the snow (it gives him a coefficient of static friction between the ski and the snow of 0.35). while skiing, he applies a 1000 n force, directed downwards and backwards, at an angle of 75deg to the horizontal (see figure). based on this information, what is: a) the magnitude of the normal reaction force (fr) between the ski and the snow, b) the magnitude of the force trying to cause sliding (fslide) between the ski and the snow, and c) what is the magnitude of the limiting value of friction (flim) d) will the ski slip?

Answer 1

• The sliding force is 966 N

• The frictional force is 90.65 N

• The normal reaction is 259 N

Frictional force is a force that opposes the relative motion or tendency of such motion of two surfaces in contact. It acts parallel to the surfaces in contact and is dependent on the nature of the surfaces and the force pressing them together.

The normal reaction is;

mgCosθ

= 1000Cos 75

= 259 N

The force of friction = 0.35 * 1000Cos 75

= 90.65 N

Net sliding force = mgsinθ

= 1000 * Sin 75

= 966 N