Topic: Dynamics
Concepts: Limiting cases, Statics

Solution:

We consider three times $t_1<t_2<t_3$ during the rotation. Time $t_1$ is the original setup where we have

by balancing forces. Time $t_2$ is when the tensions swap,

Time $t_3$ is the final setup where we have

since it can’t have a horizontal component $T_{2x}=0$ which means

We now go through the possible choices:

• A) Not correct since comparing $t_2$ to $t_1$ shows that $T_1$ increased.
• B) Not correct since comparing $t_3$ to $t_2$ shows that $T_1$ decreased.
• C) Not correct since comparing $t_2$ to $t_1$ shows that $T_2$ decreased.
• D) Correct since $T_2=0$ at time $t_3$.
• E) Not correct since comparing $t_2$ to $t_1$ shows that $T_2$ is already decreasing in the beginning.

so the answer is D.