This is not a homework problem. It was a problem posed by my professor at the end of the semester but had me puzzled for a while. I was able to satisfactorily solve it for the case when gravity is not present but I was not so successful with gravity. The question is: to determine the trajectory of the mass m1, in terms of -mass (m2), -initial length (initial radius r0) of the pendulum and -the initial angle (theta0) that the string makes with respect to the side of the table and -the initial distance of m2 from the pulley nearest to it (x0). Solution would be appreciated. Or, explanation of why a college freshman can not solve such a problem would also do. Thank you. H.G.