$A$ ring and a disc roll on a horizontal surface without slipping with the same linear velocity. If both have the same mass and the total kinetic energy of the ring is $6 \ J$,then the total kinetic energy of the disc is: (in $/2 \ J$)

In a bicycle,the radius of the rear wheel is twice the radius of the front wheel. If $r_F$ and $r_r$ are the radii,and $v_F$ and $v_r$ are the speeds of the topmost points of the wheels respectively,then:

$A$ disc is performing pure rolling on a surface. The positions of $P$ and $Q$ at an instant are shown in the figure. $C$ is the center of the disc. Which of the following is true for their velocities at the instant when $P$ and $Q$ are at the same distance from the center?

$A$ circular disc of mass $0.41 \ kg$ and radius $10 \ m$ rolls without slipping with a velocity of $2 \ m/s$. The total kinetic energy of the disc is ....... $J$.

$A$ solid homogeneous sphere of mass $M$ and radius $r$ is moving on a rough horizontal surface,partly rolling and partly sliding. During this kind of motion of this sphere,

$A$ solid sphere of mass $500 \ g$ and radius $10 \ cm$ rolls without slipping with a velocity of $20 \ cm/s$. The total kinetic energy of the sphere will be ........ $J$.