If a container of dried beans with a table tennis ball at the botton is shaken what happens to the center of gravity of the container?

Since the tennis ball density is less then the density dried beans the tennis ball will tend to rise and float on top of the dried beans. This would be equivalent to wood floating on water. So depending of the time and how vigorous the shaking is the ball will rise and the volume of tennis ball replaced with more dried beans.

The Center of Gravity (CG) will be lowered.

Ralph Schorr, P.E.