Problem 5-102 Friction force - Part 7

A skier of mass \(79\; kg\) is sliding at constant velocity down a slope inclined at \(8.3^\circ\) to the horizontal. Determine the magnitudes of:

(a) the normal force exerted on the skier.
(b) the frictional force exerted on the skier.

Accumulated Solution

FBD of skier

FBD

\(a_x = a_y = 0 \\ mg \sin \theta - F_f = 0 \\ F_f = 1.1\times10^2\; N \; \text{ (answer to part (b))}\)

What is the sum of the forces in the \(y\) direction?

(A)   \(F_N + mg \sin \theta\)

(B)   \(F_N + mg \cos \theta\)

(C)   \(F_N - mg \cos \theta \)

(D)   \(F_N - mg \sin \theta\)