12/6  There was an error in the original version of
      the Test 5 Key that was placed at the Noble Copy
      Center.  That version was replaced today.  If
      you have the original version, the error is in
      MC #6; the correct answer is 0.8 s.  If you get
      your test back from you TA today, you should
      double-check that #6 has been graded correctly.
      Thanks and sorry for the error.  GBA

12/4  The Test 2-5 Keys are now available at the Noble
      Library Copy Center. GBA

9/22  The Test 1 Key is now available at the Noble
      Library Copy Center. GBA

9/06  The Old Tests are now available at the Noble
      Library Copy Center. GBA

9/06  Several students asked about the "flowerpot" 
      problem.  Here's my solution.  Divide window 
      height by delta t (time to pass) giving the 
      average speed while passing.  This is also 
      the instantaneous speed at the middle of the 
      interval timewise.   Therefore, multiply half 
      the delta t times g and subtract this from the 
      average speed, giving the speed at the top of
      the window.  Once you know the speed at the 
      top of the window the rest is easy.  There are
      several other solutions.  For example, if you
      like to do algebra, you can write the position 
      equation for the instant when the top of the 
      window is passed (this equation will have two 
      unknowns), repeat for the instant that the
      bottom of the window is passed (same two 
      unknowns), and solve the system of equations.  
      GBA

9/05  There was another temporary email disruption on
      9/05.  Some emails may have been lost.  If you
      sent an email on 9/05 and did not receive a
      reply, please send again. Thanks. GBA

9/01  My email disruption has now ended (5 PM Fri 9/01).
      If you sent an email on Thur 8/31 or before Fri
      9/01, and did not get a reply, you might want to
      resend the email.  Thanks for your patience. GBA

8/31  My main email address is connected to a computer
      in the basement of Goldwater.  There is some problem
      over there today (turned out to be an electrical 
      fire), so my email is temporarily not working.  If 
      the Goldwater problem is not solved soon, I will 
      switch to an alternate email address.  Thanks for 
      your patience. GBA

8/19  No updates yet.