A child is standing with his two arms outstretched at the center of a turntable that is rotating about its central axis with an angular speed $w_0$ Now the child folds his hands back so that the moment of inertia becomes 3 times the intial values.The new angular speed is

Question

$\begin{array}{1 1} 3w_0 \\ \frac{w_0}{3} \\ 6 w_0 \\ \frac{w_0}{6} \end{array}$