Kylie is walking through the cafeteria. She has not seen that her
classmate has just spilled her glass of juice. As Kylie, who weighs 400 N
steps on the juice, the coefficient of friction between her and the floor
is suddenly decreased to 0.035. What is the force of sliding friction
between Kylie and the slopy floor?
Without friction, your foot would slide back, moving back relative to the floor, as shown in Figure 5.2. Static friction opposes this motion, the motion that would occur if there was no friction, and thus static friction is directed forward.
