I made a pair of sign errors at the end of the lecture
on Fri 2/11. First, I wrote Tsin(theta) for the x-component
of the tension, when it should have been -Tsin(theta). Then
I made a second sign error, using mg for W when I should have
used -mg, so that the two errors together gave the positive
angle I was looking for. Here is an explanation and the
correct work. This is also available as a pdf file and at
the Noble Library Copy Center. I apologize for any confusion
this might have caused. GBA.