A pendulum consists of a light rigid rod of length 250mm, with two identical uniform solid spheres of radius 50mm attached one on either side of its lower end. Find the period of small oscillations (a) perpendicular to the line of centers, and (b) along it.
Period = 2*pi*sqrt(I/MgR)
Parallel axis theorem: I = Icm + Md^2
The Attempt at a Solution
I tried simply applying the parallel axis theorem to a ball using Icm = 2/5mr^2 and d = sqrt(.25^2+.05+2) but this yields and incorrect answer. I believe this method would be wrong because it would give the same answer for both parts, which is not the case
ps not sure if this belongs in advanced or not