Which of the following statements is incorrect for a spherical body rolling without slipping on a rough horizontal ground at rest?

$A$ sphere rolls without slipping. The radius of gyration about an axis passing through its center of mass is $K$. If the radius of the sphere is $R$,what fraction of the total energy is in the form of rotational kinetic energy?

$A$ uniform disc of mass $0.5\,kg$ and radius $r$ is projected with velocity $18\,m/s$ at $t = 0\,s$ on a rough horizontal surface. It starts off with a purely sliding motion at $t = 0\,s$. After $2\,s$ it acquires a purely rolling motion (see figure). The total kinetic energy of the disc after $2\,s$ will be $..............J$ (given,coefficient of friction is $0.3$ and $g = 10\,m/s^2$).

$A$ solid disc rolls clockwise without slipping over a horizontal path with a constant speed $v$. Then the magnitude of the velocities of points $A, B$ and $C$ (see figure) with respect to a standing observer are:

$A$ wheel of radius $R$ rolls on the ground with a uniform velocity $v$. The relative acceleration of the topmost point of the wheel with respect to the bottommost point is

The ratio of the total kinetic energy to the rotational kinetic energy for a rolling disc is: