Question

When rolling a ball down a plank what is the difference between a solid ball and a hollow ball besides the obvious mass difference

Answer 1

i think the questioner might want to hear, that the hollow ball is slower (given, they have the same diameter and mass).

If thats not intuitive, think about how the moment of inertia is calculated and how the potetnial energy is converted to kinetic and rotational energy.

Answer 2

there is apparantly a different formulae for calculating the velocity

Answer 3

why would there be a different formula?

(there isn't)

Answer 4

There is