Rotational Motion Question 183
Question: A sphere of mass ?m? is given some angular velocity about a horizontal axis through its 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
Options:
A) Zero
B)$(7/5)\mu g$
C) $\mu g$
D) $2\mu g$
Show Answer
Answer:
Correct Answer: C
Solution:
[c] FBD for sphere and block
$a _{1}=\frac{f _{r}}{m}=\frac{\mu mg}{m},a _{2}=\frac{f _{r}}{m}=\frac{\mu mg}{m}$
$\overset{\to }{\mathop{a _{1}}}=\mu g\hat{i},\overset{\to }{\mathop{a _{2}}}-\mu g\hat{i}$
