Venturimeter
It is a device used for measuring the rate of flow of liquid t pipes . Its working is based on Bernoulli ’ s theorem .
Rate of flow of liquid ,
where , a1 and a2 are area of cross-sections of tube at bra and narrower part and h is difference of liquid columns in ver tubes .
Torricelli ’ s Theorem
Velocity of efflux ( the velocity with which the liquid flows out orifice or narrow hole ) is equal to the velocity acquired by a falling body through the same vertical distance equal to the dep orifice below the free surface of liquid .