Ideal Fluid And Bernoulli's Principle

At the bottom of a container, there is a small hole covered by a lid. The air pressure inside the container is $p$, which is much less than the external atmospheric pressure $p_0$ (i.e., $p \ll p_0$). The lid is suddenly removed.

A simple Venturi meter, as shown in Figure, is a horizontal tube with varying cross-sections used to measure fluid flow rate. The flow rate $Q$ is the volume of fluid passing a cross-section per unit time, given by $Q=vS$, where $v$ is the fluid velocity and $S$ is the cross-sectional area. The difference in fluid height, $h$, in the two vertical tubes at sections A and B can be used to determine $Q$.

Water flows at $v_1 = 5.0$ m/s through a pipe section with a cross-sectional area of $S_1 = 4.0$ cm$^2$. The pipe descends by a height of $h=10$ m to a lower section where the cross-sectional area is $S_2 = 0.8$ cm$^2$. The pressure in the upper section is $P_1 = 1.50 \times 10^5$ Pa. Use the density of water $\rho = 1000$ kg/m$^3$ and the acceleration due to gravity $g=9.8$ m/s$^2$.

On the floor, there is a bucket full of water, where the water surface is at a height H. A small hole is opened on the bucket wall at a depth h below the water surface.