A weightless rigid rod \( A B \) of length \( l \) connects two equal masses \( m \) one particl...

A weightless rigid rod \( A B \) of length \( l \) connects two equal masses \( m \) one particle is fixed at the end \( B \) and the other at the middle of the rod as shown in the figure- \( 5.131 \). The rod can rotate in the vertical plane freely around the hinge point \( A \).
         Figure \( 5.131 \)
Choose the correct option(s).