A solid sphere of mass 2kg is making pure rolling on a horizontal...

Let velocity of centre of mass of sphere be $v$.

Total kinetic energy of solid sphere is $KE = \dfrac{1}{2}m{v}^{2} + \dfrac{1}{2}I{\omega}^{2}$, where, $I$ is moment of inertia of the solid sphere about the axis passing through it's centre of mass and $\omega = \dfrac{v}{R}\left(\text{pure rolling condition}\right)$.

Therefore,

$2240 = \dfrac{1}{2}2 ( v{)}^{2} + \dfrac{1}{2}\left[\dfrac{2}{5} ( 2 ) {R}^{2}\right]{\left(\dfrac{v}{R}\right)}^{2}$

$⇒ 2240 = {v}^{2} + \dfrac{2}{5}{v}^{2}$

$⇒ v = 40m{s}^{- 1}$.