A solid sphere is let go from rest at the top of a slope at 25°, 4.0 m long, and rolls without…

Rolling without slipping: $v = \omega R$. Kinetic energy: $\tfrac12 Mv^2\left(1 + \dfrac{I}{MR^2}\right)$. Down a slope: $a = \dfrac{g\sin\theta}{1 + I/MR^2}$ and $v = \sqrt{\dfrac{2gh}{1 + I/MR^2}}$; static friction $f = \dfrac{I/MR^2}{1 + I/MR^2}\,mg\sin\theta$ does no work.