COMMENTS ON SECOND PROBLEM SET - FALL 2002

	General:  Depending on your approach, you might want to try
Problem 2.3 before Problem 2.1;  Problem 2.3 has partial answers in
the back, so you can check to make sure you're doing this sort of
problem properly.

	2.1: The "small velocity-dependent air friction" should be
taken to mean "underdamped," so if you, like me, treat this as a math
problem instead of a physics problem, it will be tougher.  For
starters, assume that the answer to part (d) is real and positive.
	For part (e), you want to reproduce some but not all of what
was done in lecture 9-16-2002.  Assuming a "high-Q" oscillator will
make life much simpler, but as I read the problem, there is no reason
to assume that the driving frequency is close to the frequency of
undamped, undriven oscillations.
	The important thing is to state clearly any assumptions you
make.

	2.2: French is rather sparing of details for this one (I think
this is done on purpose). You'll have to make some asssumptions about
the oscillator, and if you introduce notation not given in the
problem, be clear about what you mean.

	2.3: From the answer in the back, A(omega) diverges as omega
goes to zero.  You should be able to explain why.  Parts (c) and the
added part (d) require you to make plots, and this would be a great
time to use some plotting program.  Details on request.

	2.4:  Again, this is quite similar to the example done in
lecture, but that example had the driving frequency much lower than
the  resonance frequency.
	Also, note that phase angles are not requested in any of the
answers.  It's easy enough to tell what the difference (phi - delta)
is from the steady-state output, and delta _could_ be found from the
determined values of k, omega and b, but that's not part of the
problem as asked.  You may recall from lecture 9-16-2002 that in doing
a related example, Prof. Wyslouch indeed said something to the effect
that the phases could be found, but he declined to do so.  This more
or less means you don't have to.