From jxhu at MIT.EDU Mon Oct 2 14:58:55 2006 From: jxhu at MIT.EDU (Xiaojie Hu) Date: Mon, 02 Oct 2006 14:58:55 -0400 Subject: [Unified-mailman] Unified: This week's quiz Message-ID: <1159815535.26960.10.camel@unified-2.mit.edu> Hi All, This week's Fluids exam will remain as scheduled. (At 9 am on Friday, Oct. 6). There had been some requests to change this Friday's quiz because there is a 1.00 exam on the same day. The staff examined several alternatives, but none proved feasible. Although we try very hard to avoid exam conflicts, it is occasionally unavoidable because natural points for exams in courses often fall at the same time. Exam review for fluids will occur in recitation Tuesday and Thursday. - Jenny From drela at MIT.EDU Mon Oct 2 19:34:53 2006 From: drela at MIT.EDU (Mark Drela) Date: Mon, 02 Oct 2006 19:34:53 -0400 Subject: [Unified-mailman] Quiz reviews Message-ID: <200610022334.k92NYrwC000797@orville.mit.edu> Folks, As Jenny mentioned, we will be having the Fluids quiz reviews in the Tue and Thu recitations this week. Since there isn't enough time to review everything in detail, I will select topics by popular demand, in a Q&A format. So please think about what you would *most* like to review. I suggest that you also bring the quiz crib sheet as a handy topic list. MD From drela at MIT.EDU Tue Oct 3 22:43:57 2006 From: drela at MIT.EDU (Mark Drela) Date: Tue, 03 Oct 2006 22:43:57 -0400 Subject: [Unified-mailman] Systems Lab 4 In-Reply-To: Your message of "Tue, 03 Oct 2006 16:56:33 EDT." <000301c6e72e$68fe5c90$8000d712@trip> Message-ID: <200610040243.k942hvIM024288@orville.mit.edu> >I had a few questions about the Systems Lab 4 assignment. >In the part where we analyze stage 2 and 3, it asks us to find >the exit velocity of the rocket and the thrust. I worked them >both out and found exit velocity and thrust as dependent >on volume of air. However, volume of air is dependent on >time and exit velocity. >So when I plug the equation for volume into exit velocity >and try to solve for exit velocity as a function of time, >I get an extremely complicated equation that would take >a very long time to solve. The volume of air at any time level is an auxilliary quantity which is a function of only the state variables at that same time level. In particular, the air volume depends on the water mass, which in turn depends on the total mass state variable m_i. There's no need to solve differential equations for the air volume, or whatever you are trying to do. MD From kristina at MIT.EDU Wed Oct 4 13:59:19 2006 From: kristina at MIT.EDU (I. Kristina Lundqvist) Date: Wed, 4 Oct 2006 13:59:19 -0400 Subject: [Unified-mailman] Unified: This week's quiz In-Reply-To: Message-ID: <005601c6e7de$d14a6ef0$19062212@Lillk> Dear students, Given the class sizes of both unified and 1.00 we could not find a compatible date to reschedule either exam. As noted in the earlier email from the unified staff, you are expected to take both exams on their scheduled dates. If there are other specific constraints, please feel free to email me. ..IKL -- Kristina Lundqvist Assistant Professor of Aeronautics and Astronautics Embedded Systems Laboratory Massachusetts Institute of Technology 77 Massachusetts Avenue, Room 33-318 Cambridge, MA 02139, USA ph: 617-452-2550 email: kristina at mit.edu http://web.mit.edu/~kristina From jxhu at MIT.EDU Fri Oct 6 15:51:41 2006 From: jxhu at MIT.EDU (Xiaojie Hu) Date: Fri, 06 Oct 2006 15:51:41 -0400 Subject: [Unified-mailman] Unified: OH next week Message-ID: <20061006155141.ftn91qtyc18kg0g4@webmail.mit.edu> Hi All, Due to the Monday holiday, the regularly scheduled Monday office hours have been shifted to Tuesday, October 10. Have a good weekend! - Jenny