Aconstant friction force of 25 nacts on a 65 kg skier for 20
s. whatis the skier's change in velocity?

The skier's change in velocity is 7.69 meters per second.

Explanation:

The Newton's second law tells force is equal to the change on the linear momentum of a body:

If we approximate the differential to :

Using that linear momentum is mass times velocity:

Solving for :

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