A string with a lead ball of mass m is slowly pulled upward through a small hole. Consider the work done on the system during this process. Find the change in energy and the frequency of this pendulum during this "adiabatic process", assuming the amplitude of the pendulum to be small.
Sorry I don't have a picture.
(Imagine the situation of the wire holding the chandalier in your home being slowly pulled up through a small hole through the roof while it is slowly oscillating in one dimension, or in a single plane.)
v/r,
Set up the equations!
This isn't that hard a modeling problem. You just have to be careful to set up all of the equations for all the parts. Obtaining a solution is potentially quite a bit harder. You should at least set up the equations yourself -- then we might be able to pitch in and help.
Picture
Here's a picture of it.