A package is sliding from rest down an incline at an angle phi, and encounters a rough section that starts at height 2h and ends at height h. The starting point for the package is at height xh, and the kinetic friction coefficient between the package and the rough section is mk.
a) For what minimum value of x (i.e. xmin) will the package make it all the way through the rough section without stopping?
b) Assuming the package has passed the rough section, what is its speed v at the bottom of the incline?
c) Compute xmin and v from parts (a) and (b) if the angle phi=45 degrees, coefficient of kinetic friction=1.2, h=4m, and x=3