A sphere of mass ' $m$ ' is given some angular velocity about a $m$ horizontal axis through its $\pi$ centre…
A sphere of mass ' $m$ ' is given some angular velocity about a $m$ horizontal axis through its $\pi$ centre and gently placed on a plank of mass ' $m$ '. The coefficient of friction between the two is $\mu$. The plank rests on a smooth horizontal surface. The initial acceleration of the plank is
zero
(7 / 5) $\mu \mathrm{g}$
$\mu \mathrm{g}$
$2 \mu \mathrm{g}$
Solution
FBD for sphere and block $a_{1}=\frac{f_{r}}{m}=\frac{\mu m g}{m}, a_{2}=\frac{f_{r}}{m}=\frac{\mu m g}{m}$
$\vec{a}_{1}=\mu \mathrm{g} \hat{i}, \vec{a}_{2}=-\mu \mathrm{g} \hat{i}$
$\stackrel{f_{r}}{\longleftarrow_{a}}$
,
,