Q134 / 160 · AP EAMCET 2011 · Physics

A thin hollow sphere of mass $m$ is completely filled with a liquid of mass $m$. When the sphere rolls with a velocity $v$, kinetic energy of the system is (neglect friction)

  • A
    $\frac{1}{2} m v^2$
  • B
    $m v^2$
  • Correct answer
    C
    $\frac{4}{3} m v^2$
  • D
    $\frac{4}{5} m v^2$

Solution

$\begin{aligned} \text { Total energy } & =\mathrm{KE}+\text { rotational } \mathrm{KE} \\ & =\frac{1}{2}(2 m) v^2+\frac{1}{3} m v^2 \\ & =\frac{4}{3} m v^2\end{aligned}$

Hence, the correct answer is option: 'C'.

Relevant Questions