A solid sphere is in rolling motion. In rolling motion a body possesses translational kinetic energy (K_t ) as well as rotational kinetic energy (K_r) simultaneously. The ratio K_t : (K_t + K_r ) for the sphere is : 

5 : 7

K_t = \(\frac{1}{2}m v^2\)

K_t + K_r = \(\frac{1}{2}m v^2\) + \(\frac{1}{2}I \omega^2\)

K_t + K_r = \(\frac{1}{2}m v^2\) + \(\frac{1}{2} (\frac{2}{5}m r^2) (\frac{v}{r})^2 \)

\(\frac{K_t}{K_t + K_r}\) = \(\frac{5}{7}\)