Answer: Find Second Moment of Mass & Energy for a Taurus w/E=mc2

[colinbeaton1]

What could we learn if we found the second moment of mass for a taurus and use E = mc2 to find second moment of energy?

 

[Simon Bridge]

We may be able to learn if a red rag has any effect ("taurus" means "bull") - perhaps you mean a "torus"? Sort of a doughnut shape?

The second moment of mass is just the moment of inertia.
So we know what that is.

E=mc^2 would be the rest-mass energy of something.
Just blindly substituting a rest-mass energy density for mass in the moment of inertia calculation will still get you the (non-relativistic) moment of inertia as before - just in different units.