In the given question with constant angular velocity. It asks us to find longitudinal stress at each of the positions. Now I'm not even sure what longitudinal stress is but here is what I tried as A is the farthest it will have the highest Radius and hence highest centripetal force. Therefore component of tension should be the highest at A. But the answer is given is that it's minimum at A. Can someone tell me where am I going wrong?
Hint: It depends on how much mass it outside the 'radius of rotation'.
For example at B and C, there is tension there, as a centripetal force is needed to make the half circle (green) between B and C rotate. You would need to integrate $\delta m \times \omega^2r$ for each mass element in the green section, where $r$ is the distance of the mass element from $O$.
At A there is no mass outside that radius, so there can be low tension as a centripetal force isn't required.