Is q1 a function of time
Q: Are the q_1 and q_2 functions of time or some kind of absolute position?
A: I'm assuming that this question referred to the spring mass system found on p. 5 of the lecture notes.
In this case, q1 and q2 give the positions of the masses, and as such are going to be functions of time.
The state of this system, X, is represented by the positions and velocities of the two masses [q1, q2, q1_dot, q2_dot], and we are trying to set up the equation that will give dX/dt in terms of elements of X. If we were to solve this system of equations, we'd then get q1 and q2 as functions of time and the initial conditions.
--Lindzey 18:19, 2 October 2006 (PDT)