Physics - Rotation Question with Solution | TestHub

$\begin{array}{rl}\tau =& l\alpha \\ & I=\text{ moment of inertia }\\ & \alpha =\text{ angular acceleration }\end{array}$ $\begin{array}{ll}\text{ If }& \tau =0\Rightarrow l\alpha =0\\ \text{ But }& I\ne 0\end{array}$ $\therefore \alpha =0$