A U-shaped pipe with a constant cross-section, open at the ends towards the atmosphere, 

 contains homogeneous liquid over a section of total length l . In the initial situation a valve R keeps the liquid in an asymmetrical configuration, in which the difference 

 

 in height between the free surfaces A and B is h. At a certain instant the valve R is 

 

opened and the liquid begins to oscillate. Assuming the liquid is perfect, calculate the

 

period of oscillation and the maximum velocity of the liquid with respect to the pipe.

 

A h R B