Homework for Friday, Nov 13. (due in class on Friday).
[Also, be sure to work on your POW, due Wdenesday...]
71) Consider a wire loop with the shape z=r^2/a + r^4/a^3 ,
that spins at a frequency Omega...
a) Plot the position of the STABLE equilibrium point as a function of
Omega. (Calculate it first.)
b) If you can, calculate the frequency for small oscillations about the
stable equilibrium point as a function of Omega, AND PLOT IT on a graph
with the position of the stable equilibrium points (both vs Omega).
If you cannot calculate it, try to do a rough sketch anyway. What do you learn from
the relationship between these two quantities??
62) Consider a double pendulum with equal lengths, l, and masses, m .
a) Write the Lagrangian, (you have this already)
and obtain from it the Lagrangian equations of motion .
b)Expand to lowest in order in theta1 and theta2 (for small deviations from
equilibrium).
c) Can you solve for the oscillation frequencies of this system (assuming
only small angle motion)? How many "normal modes" are there??
What is a normal mode (in general)?
What do you think they look like for this system??