# rotaional motion

Two balls of mass $${ m }_{ 1 }=56g$$ and $${ m }_{ 2 }=28g$$ are suspended on two threads of length $${ l }_{ 1 }=7cm$$ and $${ l }_{ 2 }=11cm$$ at the end of a freely hanging rod (see fig). Determine the angular velocity $$w$$ at which the rod should be rotated about the vertical axle so that it remains in vertical position![]

sorry for blurred image.