Hi Luke! On Mon, Nov 14, 2011 at 10:40 AM, Luke <hazelnu...@gmail.com> wrote: > This might be a bit off topic but I think there are enough physicists > on the list who would be interested winning in a free copy of a new > exercise book for the Feynman Lectures on Physics: > > http://feynmanlectures.info/announcement.html > > I worked out the solution, but have been told it is unacceptable > because it involves differential equations. Newton's second law is a > vector differential equation (dp/dt=F, p and F both vectors), so I'm > not clear on how the solution can involve Newtonian mechanics but not > differential equations, as stated in the problem. Maybe somebody here > can figure it out, apparently Feynman did. My solution is here: > > http://dlpeterson.com/FLP_Exercise_Challenge/solution.pdf
Haha, very nice! A few points: 1) How did you create the drawing in the pdf? 2) We did this exact example in our undergrad mechanics course at my university using a Lagrangian to derive the equations of motion. I wonder if i can redo it, I would love to put this and similar examples into my notes at theoretical-physics.net. Also with your solution, to show that one can derive the equations of motion in another way. 3) Can pydy derive the equation of motion? 4) Feynman would of course never use your systematic approach, but rather use some trick to find the solution in 2 lines 5) Point 4) is precisely why I don't like Feynman's approach to physics as a way to learn and do physical problems, but I like it as an amusement and to get new physical insight, *after* I have been able to solve the problem using a systematic approach. This is also the motivation behind theoretical-physics.net, to *only* use systematic approach and reject all "tricks". 6) If anyone finds the trick to solve the problem, I would be interested. Ondrej -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
