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**1. The problem statement, all variables and given/known data**

An object is formed by attaching a uniform, thin rod with a mass of mr = 6.94 kg and length L = 5.56 m to a uniform sphere with mass ms = 34.7 kg and radius R = 1.39 m. Note ms = 5mr and L = 4R.

What is the moment of inertia of the object about an axis at the right edge of the sphere?

**2. Relevant equations**

I = mr^2

I(rod-end)=1/3 mr^2

I(spherical shell)=2/3 mr^2

I(sphere) = 2/5 mr^2

**3. The attempt at a solution**

I figured that it would be a spherical shell going around the axis, because the whole sphere is rotating, rather that it rotating at it center of the sphere, and then the rod going around as well. I'm obviously wrong, seeing as I'm reaching out for help, but here's what I had put, I am not sure why it's wrong though, and I don't know what to do.

1/3 (m rod)(L + 2R)^2 + (2/3) (m sphere)(2R)^2

(1/3)(6.94)(5.56+2.78)^2 + (2/3)(34.7)(2.78)^2