A uniform rope a length L has a mass M. It is stretched out along aa table with a portion of the rope, x, hanging over the edge of the table. There is a coefficient of friction , u, between the rope and the table.

a. What fractional length  of the rope must be hanging off the table for it to begin to move?

b. If there is a sufficient rope hanging off the table, what is the fictional form of its velocity  as a function of x?