The uniform concrete pipe has a weight of 800 lb and is unloaded slowly from the truck bed...

The uniform concrete pipe has a weight of 800 lb and is unloaded slowly from the truck bed using the rope and skids shown. If the coefficient of kinetic friction between the rope and pipe is µk = 0.3, determine the force the worker must exert on the rope to lower the pipe at slip on the skids. The lower portion of the rope is parallel to the skids.