The circular motion of the bucket in a vertical plane under gravity is not a uniform circular motion. Assuming the critical case of the motion such that the bucket has the minimum speed at the highest point required for the water to stay put in the bucket, we can find the minimum frequency of revolution.
Data : r = 8m, g = 9.8 m/s2 , π = 3.142
Assuming the bucket has a minimum speed v = \(\sqrt{rg}\) at the highest point, the corresponding angular speed is

The minimum frequency of revolution
