## Fundamentals of Physics Extended (10th Edition)

As $\theta$ increases, $f_{s,max}$ increases.
The equation that guides the thinking in this problem is: $f_{s,max}$=Coefficient of Static Friction$\times$$F_{N}$ The coefficient of static friction is always the same, so only the normal force is taken into account. The normal force has a direct relationship with $f_{s,max}$, so as the normal force increases, $f_{s,max}$ increases. Increasing $\theta$ increases the normal force, meaning that it also increases $f_{s,max}$.