Question

A cylinder open tank of radius R and height h is filled completely with water. It is now rotated about its vertical  axis. The minimum angular speed such that the small part of bottom surface get exposed to atmosphere is 

[Given Below are the options for above question.]

Answer 1

Correct option is (B) \(\frac{\sqrt{2gh}}R\)

We know that, the equation on the free surface is

y = \(\frac{\omega^2R^2}{2g}+y_0\)

y = h

y₀ = 0

h = \(\frac{\omega^2R^2}{2g}\)

\(\omega^2=\frac{2gh}{R^2}\)

\(\omega=\frac{\sqrt{2gh}}R\)