Two uniform solid spheres of mass M and radius R0 are connected by a thin (massless) rod of length 1.6R0 so that the centers are 3.6R0 apart.
(a) Determine the moment of inertia of this system about an axis perpendicular to the rod at its center.
(b) What would be the percentage error if the masses of each sphere were assumed to be concentrated at their centers and a very simple calculation could be made?
mr^2 = moment of inertia for a point mass
The Attempt at a Solution
I'm confused. I guess it's not a point mass because I keep doing it that way but I keep getting the wrong answer. (2*1.8)=3.6 1.8 is the R and 2 for the second M.
What's the real formula I should be using for this? Thanks! I need help. :)