A straight rod of negligible mass is mounted on a frictionless pivot and masses 2.5 kg and 1 kg are suspended at distances 40 cm and 100 cm respectively from the pivot as shown. The rod is held at an angle θ with the horizontal and released.
The rod remains stationary after the release
Torque about hinge is
(2.5) g(4.5×10−2)cosθ−(1)g(100×10−2)cosθ=0
So rod remains stationary after the release.