Given are two solid spheres of the same size and weight. They both have their center of mass at their geometric center.
One of them (A
), however, has most of its mass distributed near the center (heavy center, light shell),
while the other (B
) has most of its mass at the shell (light center, heavy shell).
Now I apply a tangential force ($F$) to them (they are at rest, floating in empty space). (When the ball starts to move, let's assume the force will stay tangential to the ball, i.e., the spot on the ball's surface, that the force will be applied to, changes with rotation. So the directions of the force will continue to be the same as it was at the start.)
Assuming I put the same amount of work into both ($F \cdot s$), I guess A
will spin faster than B
, because of the different moments of inertia.
Also, both will not only gain rotation but translation too. Will they both have the same (translational) speed, or does the difference in mass distribution make a difference here too?