A water tower is drained by a pipe that extends to the ground. The top surface of the water at point $2$ is at atmospheric pressure.

Point $1$ to Point $2$ is $15$ m

a$)$ What is the pressure at point $1$ if the valve is closed $($and no water is flowing$)?$

$=$ Pa

We now want to find the volume flow rate at point $1$ when the valve is open $($and the water is flowing$).$

Assume water speed at point $2$ is negligible. Set up an equation that you can use to solve this problem. You should end up with up with a single equation with two unknowns, therefore we need to know one of the unknowns before we can use the equation.

b$)$ Based on physical grounds we already know the absolute pressure at $1$ when the valve is open and the water is flowing, what is it$?$

$=$ Pa

c$)$ Using the answer from $($b$)$ you can now find the speed of the water at $1$ when the valve is open. What is it$?$

$=$ m$/$s

d$)$ Assuming the effective cross$-$sectional area of the valve opening is $2$x$10-2$m$2,$ now find the volume flow rate at point $1.$

$=$ m$3/$s

c$)$ Using the answer from $($b$)$ you can now find the speed of the water at $1$ when the valve is open. What is it$?$

$=$ m$/$s

d$)$ Assuming the effective cross$-$sectional area of the valve opening is $2$x$10-2$m$2,$ now find the volume flow rate at point $1.$

$=$ m$3/$s