I need to know why my derivation does not work. I am attempting to derive I=2/5 mR^2
I have seen people derive it using disks but my question is why do the shells not work? Where in my set up did I go wrong??? Thanks
The Attempt at a Solution
I am attempting to use shells to do this.
Ro=p=m/v so pdv=dm
moment of inertia (I) =definite integral from r=0 to r=R (4p(pi)r^4dr)
When I solve this integral it becomes (3/5)mR^2 and not (2/5) mR^2