A small solid sphere of radius r rolls down an incline without slipping which ends into a vertical loop of radius R. Find the height above the base so that it just loops the loop

The minimum velocity at P, top of the loop, should b $v=\sqrt{g(R-r)}$  if the sphere keeps on rolling at top $v=\omega R$

$\begin{array}{l}mgh=\frac{1}{2}m{v}^2+\frac{1}{2}I{\omega }^2+mg(2R-r)\\ =\frac{1}{2}mg(R-r)+\frac{1}{2}\left(\frac{2}{5}\right)m{R}^{2}2{\omega }^2+mg(2R-r)\\ =\frac{7}{10}mg(R-r)+mg(2R-r)[\omega R=v=\sqrt{g(R-r)}]\\ =\frac{mg}{10}(27R-17r)\text{ or }h=\frac{1}{10}(27R-17r)\end{array}$