A 4.0-kg block slides down a 35° incline at a constant speed when a 16-N force is applied acting up and parallel to the incline. What is the coefficient of kinetic friction between the block and the surface of the incline?
A) 0.20
B) 0.23
C) 0.26
D) 0.33
E) 0.41

Question

Quizplus · Accepted Answer

The force of kinetic friction is equal to the applied force, which is 16 N. The normal force is equal to the weight of the block multiplied by the cosine of the angle of the incline, which is 4.0 kg * 9.8 m/s^2 * cos(35°) = 32.4 N. The coefficient of kinetic friction is equal to the force of kinetic friction divided by the normal force, which is 16 N / 32.4 N = 0.20.

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