Leshawn

One-fourth of length L is hanging down over the edge of a frictionless, table. The rope has an uniform, linear density (mass per unit length), lambda, and the end already on the table is held by a person. a) How much work does the person do when she pulls...

I am not certain how to approach this. Sure a) asks for Work = F*x, so I take the integral of F*x with F= T-mg? b) Takes center of mass, but how do you get the center of mass of something that is constantly changing its position?