A 1 lb weight is suspended from a spring. Let y give the deﬂection (in inches) of the weight from its static deﬂection position, where “up” is the positive direction for y. If the static deﬂection is 24 in, ﬁnd a differential equation for y. Solve, and determine the period and frequency of the SHM of the weight if it is set in motion.
To my understanding, the initial condition is y(0) = 24. I have a differential equation of the form $my'' + ky = 0$, and I know that m = 1, but how do I find k?