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elixir [45]
3 years ago
15

A 78−kg skier is sliding down a ski slope at a constant velocity. The slope makes an angle of 21° above the horizontal direction

. (a) Neglecting any air resistance, what is the force of kinetic friction acting on the skier? (b) What is the coefficient of kinetic friction between the skis and the snow?
Physics
1 answer:
Feliz [49]3 years ago
8 0

Answer:

274N 0.41

Explanation:

As he is sliding down in a constant speed then the force that accelerates him (weight) and the force that slows his down (friction) are equal.

then

<em>friction=mass x gravity x sin(21)</em>

Fr=78kg x 9.8m/s2 x sin(21)=274N

<em>friction= coefficient of kinetic friction x normal force of from the slope</em>

Fr= u x 78kg x 9.8m/s2 x cos(21)=274N

Fr= u x 78kg x 9.8m/s2 x cos(21)=274Nu=274/677=0.41

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