A block of mass \(10~\text{kg}\) is in contact with the inner wall of a hollow cylindrical drum of radius \(1~\text{m}.\) The coefficient of friction between the block and the inner wall of the cylinder is \(0.1.\) The minimum angular velocity needed for the cylinder, which is vertical and rotating about its axis, will be: 
\(\left(g= 10~\text{m/s}^2\right )\)

Two stones of masses \(m\) and \(2m\) are whirled in horizontal circles, the heavier one in a radius \(\dfrac{r}{2}\) and the lighter one in a radius \(r\). The tangential speed of lighter stone is \(n\) times that of the value of heavier stone when they experience the same centripetal forces. The value of \(n\) is:
1. \(3\)
2. \(4\)
3. \(1\)
4. \(2\)