You are working as a summer intern for the Illinois Department of Natural Resources (DNR) and are assigned to some initial work on water resources project. The department will be overseeing the construction of a dam to create a large fresh water lake that will be approximately 18 meters deep. A horizontal pipe 1.2 meters long and 4 cm in diameter will pass through the dam at a depth of 7 meters to allow for release of the water in emergencies and for sampling. In normal situations, a plug will secure the pipe opening.

Question

d) If the plug were to be removed, how much water would flow out in 3 hours?
ΔVOL = m3

* Physics - drwls, Friday, April 30, 2010 at 2:09am

a) A*[Po + (rho) g H]
Po is atmospheric pressure
rho is the mass density of water, 1000 kg/m^3
H is the water height above the hole, 7 m
A is the pipe inner area, pi*D^2/4, in square meters

b) A* Po

c) (rho) g H

d) A*(10,800 s)*V
where V is the speed of wather leaving the pipe.
Use Bernoulli's principle to get V.

Thanks for your help but i really cant understand what to plug in bernoulli's equation. i know the equation which is P1+.5(p)v1^2=P2+.5(p)v2^2
this problem was very hard, even the student tutors at my college were unable to figure out D. so help me with it if you can since you have got me almost to the end as i got a b and c.

Answer 1

(1/2) rho v^2 = rho g H
(1/2) v^2 = 9.8 * 7

Answer 2

alrite love you man.