How Does the Position of G Change in Different Types of Pendulum Bobs?

[rem]

Homework Statement

how will the position of g incase of a simple pendulum change in the following 3 cases
1.the bob being a hollow sphere
2.half filled with liquid
3. normal sphere.

Homework Equations

The Attempt at a Solution

 

[Gib Z]

What is g? Typically it is acceleration due to gravity, but that doesn't seem to suit this question..

 

[rem]

in the 3 cases i.e.
1.solid sphere
2.hollow sphere
3.a sphere half filled with some liquid
where will the center of mass be situated and the spheres are assumed to be made of same material