Skiing up hills:

- Unlike, flat surfaces where the
force gravity is canceled out by the normal
force, it is not when going up a hill. As shown
in the Free Body Diagram (FBD); there are two
components to the force of gravity. Therefore;
in order to ski up a hill you must not only
exceed the maximum force of friction, but must
exceed the force of gravity as well. This
becomes harder and harder as the hill gets more
steep.
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